# Aback Tools - Complete Reference for AI Agents & LLMs

> This document is the authoritative, consolidated reference for Aback Tools (abacktools.com).  
> Intended for AI agents, LLMs, and automated systems that need full context about the platform.  
> Last updated: June 2026 | Fetch `https://abacktools.com/llms-full.txt` for the latest version.

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## 1. Platform Summary

| Field | Value |
|-------|-------|
| Name | Aback Tools |
| URL | https://abacktools.com |
| Type | Free browser-based online utility platform |
| Total Tools | 1,346+ |
| Categories | 12 major categories, 80+ subcategories |
| Architecture | 100% client-side - all processing happens in the user's browser via JavaScript, WebAssembly, Web Crypto API, and Canvas API |
| Business Model | Free forever - no paywalls, no premium tiers, no signup required, no rate limits |
| Target Users | Developers, designers, content creators, students, general public |
| Data Uploads | None - files and data never leave the user's device |
| Contact | contact@abacktools.com |
| Social | X/Twitter: @devvrat_hans · LinkedIn: devvrathans |

---

## 2. Mission & Core Values

**Mission:** Provide the best free online tools that are fast, secure, and privacy-focused.

**Core Values:**
- **Privacy First:** No data collection, storage, or server processing. All computation happens locally in the user's browser.
- **Free Forever:** 100% free with zero premium tiers, hidden costs, or usage limitations.
- **No Signup Required:** Instant access to every tool without registration or email.
- **Browser-Based:** Works in any modern browser (Chrome, Firefox, Safari, Edge); no installation needed.
- **Offline Capable:** Many tools continue to work offline after the page has loaded.

---

## 3. How Tools Work (Technical)

All tools are built with JavaScript and run entirely in the browser using:

| Technology | Used For |
|------------|----------|
| Canvas API | Image processing, pixel manipulation, format conversion |
| Web Crypto API | Cryptographic operations (AES, RSA, ECDSA, key generation) |
| File API | File reading, parsing, and writing locally |
| WebAssembly | Performance-intensive operations (PDF processing, compression) |
| Tesseract.js | OCR (optical character recognition) in 15+ languages |
| pdf-lib | PDF creation, modification, and merging |
| FFmpeg.wasm | Audio/video processing in the browser |
| JSZip | ZIP file creation and extraction |

No backend server receives user data. Files, code, credentials, and personal content never leave the user's device.

---

## 4. Complete Tool Directory

### 4.1 Image Tools - 137 Tools

**Base URL:** https://abacktools.com/tools/image  
**Subcategories:** Converters · Compressors · Optimizers · Utilities

---

#### Image Converters (https://abacktools.com/tools/image/converters)

| Tool Name | URL Path | Description |
|-----------|----------|-------------|
| PNG to RAW | /tools/image/converters/png-to-raw | Convert PNG images to RAW pixel data format (RGBA/RGB/Grayscale) |
| PNG to JPG | /tools/image/converters/png-to-jpg | Convert PNG to JPG with adjustable quality (1-100%) |
| JPG to RAW | /tools/image/converters/jpg-to-raw | Convert JPG/JPEG to RAW with customizable bit depth |
| BMP to RAW | /tools/image/converters/bmp-to-raw | Convert BMP images to RAW format |
| GIF to RAW | /tools/image/converters/gif-to-raw | Convert GIF (first frame) to RAW format |
| TIFF to RAW | /tools/image/converters/tiff-to-raw | Convert TIFF images to RAW format |
| WebP to RAW | /tools/image/converters/webp-to-raw | Convert WebP images to RAW format |
| SVG to RAW | /tools/image/converters/svg-to-raw | Rasterize SVG to RAW pixel data |
| ICO to RAW | /tools/image/converters/ico-to-raw | Convert ICO icon files to RAW format |
| HEIC to RAW | /tools/image/converters/heic-to-raw | Convert iPhone HEIC/HEIF to RAW |
| AVIF to RAW | /tools/image/converters/avif-to-raw | Convert AVIF to RAW format |
| CR2 to RAW | /tools/image/converters/cr2-to-raw | Convert Canon CR2 to RAW pixel data |
| NEF to RAW | /tools/image/converters/nef-to-raw | Convert Nikon NEF to RAW |
| ARW to RAW | /tools/image/converters/arw-to-raw | Convert Sony ARW to RAW |
| DNG to RAW | /tools/image/converters/dng-to-raw | Convert DNG to RAW format |
| ORF to RAW | /tools/image/converters/orf-to-raw | Convert Olympus ORF to RAW |
| RAF to RAW | /tools/image/converters/raf-to-raw | Convert Fujifilm RAF to RAW |
| PSD to RAW | /tools/image/converters/psd-to-raw | Convert Photoshop PSD to RAW |
| TGA to RAW | /tools/image/converters/tga-to-raw | Convert TGA to RAW format |
| PCX to RAW | /tools/image/converters/pcx-to-raw | Convert PCX to RAW format |
| EPS to PCX | /tools/image/converters/eps-to-pcx | Rasterize EPS to PCX Version 5 |
| HEIC to JPG | /tools/image/converters/heic-to-jpg | Batch HEIC/HEIF to JPG/PNG/WebP with ZIP download |
| JXL to EPS | /tools/image/converters/jxl-to-eps | Convert JPEG XL to EPS format |
| JXL to CR2 | /tools/image/converters/jxl-to-cr2 | Convert JPEG XL to Canon RAW CR2 |

---

#### Image Compressors (https://abacktools.com/tools/image/compressors)

**Target-size compressors:** 10KB, 20KB, 50KB, 100KB, 200KB, 500KB, 1MB, 2MB, 5MB  
**Format-specific compressors:** JPEG, PNG, WebP, AVIF, GIF, HEIC, BMP, PSD, APNG, TGA, PCX  
**Platform-specific:** WhatsApp, WordPress, Instagram, LinkedIn, Google PageSpeed, email, iOS app, Android app  

Notable tools:
- `/tools/image/compressors/bulk-image-compressor` - compress up to 50 images simultaneously with per-image settings
- `/tools/image/compressors/jpeg-to-avif-compressor` - three-way JPEG vs WebP vs AVIF comparison with size metrics
- `/tools/image/compressors/compress-image-for-android-app` - generates all Android drawable density buckets (mdpi through xxxhdpi)
- `/tools/image/compressors/lossy-image-compressor-with-preview` - real-time before/after with SSIM perceptual quality score
- `/tools/image/compressors/compress-to-1mb` - intelligent quality reduction to hit 1MB target
- `/tools/image/compressors/compress-to-100kb` - aggressive compression to reach 100KB

---

#### Image Optimizers (https://abacktools.com/tools/image/optimizers)

- Lossless PNG compressor, transparent PNG compressor
- WebP/AVIF batch compressor, BMP compressor, RAW image compressor
- Target-size: 20KB, 100KB, 200KB
- Platform: Facebook, Shopify, Instagram, Twitter/X, Google PageSpeed, email, iOS, Android splash screen
- Format comparison tool: JPEG vs PNG vs WebP vs AVIF vs GIF side-by-side with byte savings
- Watermarked image compressor (region-aware quality mapping to preserve watermark readability)
- GIF to WebP converter, GIF to AVIF converter, GIF optimizer
- PNG to WebP, PNG to AVIF, WebP to AVIF converters/compressors

---

#### Image Utilities (https://abacktools.com/tools/image/utilities)

| Tool | URL Path | Key Features |
|------|----------|--------------|
| Image Resizer | /image-resizer | Resize by px, %, or max dimension; aspect ratio lock |
| Image to Text (OCR) | /image-to-text-ocr | Tesseract.js, 15+ languages, paragraph/word modes |
| Photo Collage Maker | /photo-collage-maker | Up to 6 photos, 13 layout templates, PNG export |
| Image Grid Splitter | /image-grid-splitter | NxM grid (3×3, 4×4, etc.), ZIP download |
| Image Dimensions Checker | /image-dimensions-checker | Width, height, file size, format, aspect ratio table, CSV export |
| EXIF Metadata Stripper | /exif-metadata-stripper | Strip GPS, camera, date metadata losslessly |
| Image Metadata Viewer | /image-metadata-viewer | EXIF, IPTC, XMP structured table, JSON/CSV export |
| Sprite Sheet Packer | /sprite-sheet-packer | JSON/CSS coordinate maps |
| Favicon Generator | /favicon-generator | Standard favicons, Apple touch icons, Android manifest icons, ZIP |
| App Icon Generator | /app-icon-generator-all-sizes | iOS and Android all required sizes, ZIP |
| Splash Screen Generator | /splash-screen-generator | iOS and Android resolutions, ZIP |
| GIF Maker & Editor | /gif-maker-editor | Stitch image/video frames locally |
| Image Canvas Cropper | /image-canvas-cropper | Crop, rotate, flip, resize with aspect ratio targets |
| Image Cropper | /image-cropper | Free-form, fixed aspect ratio, or pixel-exact |
| Pixel Art Creator | /pixel-art-creator | 8×8 to 64×64 grid, transparent PNG at 1×-16× scale |
| Passport Photo Generator | /passport-photo-generator | US 2×2in, UK 35×45mm, EU, India, Canada, 6 more standards |
| ASCII Art from Image | /ascii-art-from-image | 6 character sets, color mode, configurable width |
| Image Flip & Rotate | /image-flip-rotate | Any degree rotation, horizontal/vertical flip |
| Image Border Adder | /image-border-adder | Solid color, gradient, dashed, polaroid, rounded corners |
| Image Format Identifier | /image-format-detector | Magic-byte detection for 15+ formats, flags extension mismatches |
| Color Palette Extractor | /color-palette-extractor | Dominant colors via canvas pixel quantization |
| Image Color Picker | /image-color-picker | Pixel-accurate eyedropper, HEX/RGB/HSL, magnifier |
| Photo Filters & Effects | /photo-filters-effects | 9 presets + brightness/contrast/saturation/blur/sharpen sliders |
| Base64 to Image | /base64-to-image-decoder | Paste Base64 data URI, preview and download |
| Image to Base64 | /image-to-base64-encoder | Data URI and raw Base64 for CSS/HTML/JSON/API |
| Image Stacker & Overlay | /image-stacker-overlay | 16 blend modes, opacity, scale, position controls |
| Thumbnail Generator | /thumbnail-generator | 150px/300px/600px/1200px and custom sizes, ZIP download |
| Color Blindness Simulator | /color-blindness-simulator | Protanopia, deuteranopia, tritanopia, achromatopsia, 4 more CVD types |
| Color Palette Generator | /color-palette-generator | Complementary, triadic, analogous, split-complementary, tetradic, monochromatic |
| Complementary Color Finder | /complementary-color-finder | All harmony types, HEX/RGB/HSL, CSS export |
| Screenshot Framer | /screenshot-framer | Phone/tablet/laptop device mockups |
| App Store Screenshot Resizer | /app-store-screenshot-resizer | Apple App Store and Google Play exact dimensions, batch ZIP |
| Add Text to Image / Meme Maker | /add-text-to-image | Impact font, custom colors, outline, alignment |
| Image Watermark Adder | /image-watermark-adder | Text or logo, 9 anchor positions, opacity, rotation |
| Background Remover | /background-remover | AI-powered segmentation, runs locally, transparent PNG output |
| Image Compression Ratio Calculator | /image-compression-ratio-calculator | BPP, Shannon entropy, format efficiency metrics |
| Image PSNR Calculator | /image-psnr-calculator | Peak Signal-to-Noise Ratio, per-channel (R/G/B), MSE |
| Duotone Image Generator | /duotone-image-generator | 9 presets or custom two-color duotone |
| Image Sharpener | /image-sharpener | Unsharp Mask or Laplacian, adjustable strength/radius/threshold |
| Image DPI Checker & Changer | /image-dpi-checker | Read DPI metadata, change without resampling, 6 print presets |
| Image Histogram Viewer | /image-histogram-viewer | R/G/B/luminance distributions, peak/mean values, CSV export |
| Pencil Sketch & Cartoon Effect | /pencil-sketch-cartoon-effect | Emboss, edge-detect, halftone, cartoon via canvas convolution |
| Photo to Painting Effect | /photo-to-painting-effect | Oil painting, watercolor, impressionist, pastel, gouache (Kuwahara filter) |
| Image Tiler | /image-tiler | Seamlessly tiled output up to 8000×8000px, 4 repeat modes |
| Image Noise Reducer | /image-noise-reducer | Gaussian blur or Median filter, before/after preview |
| Screenshot to Clean PNG | /screenshot-to-clean-png | Auto-trim whitespace, add browser/device frame |
| Image Side-by-Side Comparer | /image-side-by-side-comparer | Draggable vertical divider, zoom, download |

---

### 4.2 Data Tools - 557 Tools

**Base URL:** https://abacktools.com/tools/data  
**Subcategories:** Converters · Archive · Minifiers · Beautifiers · Obfuscators · Comment Removers · Formatters · Validators · Analyzers · Generators · Dev Utilities · Text Utilities · Text Compressors

---

#### Data Converters (https://abacktools.com/tools/data/converters)

**Data Format Converters:**
- JSON → YAML, YAML → JSON, XML → YAML, XML → JSON, JSON → XML
- CSV → YAML, TSV → YAML, JSON → CSV, CSV → JSON (nested keys, type inference, delimiter controls)
- Large Excel (.xlsx/.xls/.ods, 50,000+ rows) → JSON/CSV
- JSON → TOON, YAML → TOON, CSV → TOON (Token-Oriented Object Notation - reduces LLM token usage 30-60%)
- JSON → TypeScript Interface, JSON → Python Dataclass/Pydantic Model, JSON → Go Struct
- JSON → Zod Schema, JSON Schema Generator (Draft-07 and 2020-12)
- JSON Merge Tool (deep-merge with 5 conflict strategies), YAML Merge Tool
- CSV Delimiter Detector and Normalizer, CSV Encoding Detector, CSV Joiner & Column Splicer
- BOM Detector and Remover, Unicode and Encoding Repair Tool, Newline and Line Ending Fixer
- Lua → JSON Table, Postman JSON → cURL, OpenAPI Example Payload Generator
- SQL → NoSQL Query Converter (MongoDB find()/aggregate()), JSON to SQL Safety Checker
- LLM Output JSON Guardrail Validator (parse errors, risky content, guardrail concerns)
- YAML Canonical Normalizer, GraphQL → REST Mapping Helper
- LESS → CSS Compiler, SCSS → CSS Compiler, CSS → Tailwind Converter, Tailwind → CSS Converter
- CSS Variable Extractor (CSS/JSON/TypeScript/SCSS/Markdown export)
- HTML → JSX Converter, JSX → HTML Converter
- Markdown → HTML, Markdown → PDF, Markdown → Word/DOCX
- Markdown Live Editor & PDF Exporter
- Markdown → Slack/Teams Format (mrkdwn)
- Markdown → YAML (frontmatter extraction)
- XML → PDF, XML to Compressed JSON (three-way size comparison)
- Properties → YAML, INI → YAML, ENV → YAML, TOML → YAML, HCL → YAML, HOCON → YAML, SQL → YAML, HTML → YAML

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#### Comment Removers (https://abacktools.com/tools/data/comment-removers)

30+ languages: JavaScript, TypeScript, Python, Java, C, C++, C#, Go, Rust, Kotlin, Swift, Dart, PHP, Ruby, R, Lua, SQL, HTML, CSS, XML, YAML, TOML, INI, Dockerfile, Terraform HCL, Nginx config, Apache config, Makefile, Protobuf, GraphQL, Shell/Bash

---

#### Formatters (https://abacktools.com/tools/data/formatters)

SQL, Lua, CSS, JavaScript, HTML, TOML, Dart, Bash, Shell (POSIX/ksh/zsh), GraphQL, Kotlin, Nginx, Terraform/HCL, Dockerfile, Protobuf, Apache, Makefile, INI/CFG, Groovy/Jenkinsfile/Gradle, Rust, R, Swift, HOCON, Verilog/SystemVerilog, VHDL, Puppet, Ansible, CMake, Markdown Table Repair, HTML Broken Tag Fixer, Newline/Line Ending Fixer, Unicode/Encoding Repair, BOM Detector/Remover, Lockfile Conflict Resolver

---

#### Validators (https://abacktools.com/tools/data/validators)

**Config & Data Formats:** YAML, JSON Schema, XML/XSD, TOML, INI, HOCON, TOON, CSV, TSV, ENV/dotenv, HTML, CSS, RSS/Atom, JSON Lines/JSONL

**Developer Tooling:** JavaScript syntax, Python syntax, Shell script syntax, TypeScript type errors, Java compiler errors, C/C++ compiler errors, C# build errors, Go build errors, Rust compiler errors, PHP/Ruby/Kotlin/Swift/Dart errors, SQL syntax, SQL query validator, SQL performance smell checker, SQL index recommendation

**Web & SEO:** robots.txt, robots.txt rule conflict explainer, sitemap XML, sitemap index splitter, Open Graph, Twitter Card, hreflang, hreflang return-link, canonical URL, meta robots, orphan page finder, duplicate content finder, keyword cannibalization checker, redirect chain checker, redirect rule tester

**Security & Auth:** JWT decoder/validator, JWT expiry countdown, OAuth redirect URI, OAuth scope comparator, secret exposure scanner, CSP nonce/hash generator, mixed content checker, SSL certificate health checker, cookie attribute security, CORS preflight debug, CSP builder

**Email & DNS:** SPF record validator, SPF flattening risk estimator, DKIM record validator, DKIM selector planning helper, DMARC record validator, DMARC rollout planner, DNS record validator, domain propagation checker, DNS propagation ETA estimator, DNS TTL strategy calculator, email subject line length checker, SMS character counter

**Infrastructure & DevOps:** Kubernetes YAML, Kubernetes resource name sanitizer, Kubernetes label/annotation validator, Docker Compose, Dockerfile best practices, Nginx config, Apache config, Caddy config, HAProxy config, Terraform HCL, Helm values, GitHub Actions, GitLab CI YAML, Jenkinsfile, Ansible playbook, service worker debugger

**Frontend & Bundlers:** tsconfig, Webpack config, Vite config, Next.js config, Rollup config, ESLint config, Prettier config, Stylelint config, PostCSS config, package.json dependency health, npm scripts, Yarn workspaces, monorepo path alias, circular dependency detector, missing env variable detector, feature flag rule validator, A/B test configuration validator

**GraphQL & API:** GraphQL schema, GraphQL query cost estimator, REST endpoint naming consistency, API versioning strategy, Protobuf syntax, Protobuf field number gap checker

**Structured Data & Schema:** JSON-LD, Schema.org structured data, FAQ schema, HowTo schema, breadcrumb schema, organization schema, product schema, review snippet eligibility, PWA manifest, app-ads.txt, ads.txt, GA4 event names, GA4 setup, consent mode, cookie banner compliance

**Utilities:** UUID/GUID validator, UUID version inspector, cron expression validator, cron to human-readable translator, interactive cron scheduler, semver validator, semver range intersections, regex explain & test, regex from plain English generator, slug generator, filename sanitizer, bulk case converter, ISO 8601 date normalizer, epoch milliseconds converter, timezone meeting overlap finder, IBAN format checker, VAT number validator, phone number E.164 formatter, address line splitter, QR payload generator, password policy regex builder, consent text readability checker, webhook signature validator, payment webhook event validator, rate limit header analyzer, HTTP headers inspector, HTTP header diff checker, prompt injection risk checker for AI apps

---

#### Analyzers (https://abacktools.com/tools/data/analyzers)

- CSV viewer (interactive, search, sort, statistics panel)
- Chart builder from CSV (bar, line, pie, scatter, PNG download)
- Data type guesser (SQL and TypeScript type inference from values)
- Meta description checker (15+ SEO signals, length, keyword density)
- JavaScript bundle bloat analyzer
- LCP resource finder, TTFB analyzer, render-blocking resource detector
- Image optimization checker, web font loading analyzer, caching header analyzer
- HTTP header security checker (CSP, HSTS, XSS protection, Frame options, server leakage)
- Service worker debugger
- tsconfig analyzer with fix suggestions
- package.json dependency health checker
- npm scripts validator, Yarn workspaces validator, monorepo path alias validator
- Circular dependency detector, missing env variable detector, env key type validator
- Feature flag rule validator, A/B test configuration validator
- Accessibility: contrast checker (WCAG AA), landmark checker, form label checker, keyboard navigation tester
- Broken internal/external link checker
- HTML email compatibility checker (major clients: Gmail, Outlook, Apple Mail, etc.)
- Google AdSense eligibility precheck (weighted scoring across 9 criteria)
- Open Graph preview (Facebook, X, LinkedIn, WhatsApp, Slack, Discord)
- Favicon checker (ICO, PNG, SVG, Apple Touch, manifest, Microsoft tiles, theme color)
- SQLite browser & executor (100% local, upload .db or .sqlite files)
- JSON to table renderer (sortable, filterable, CSV export)
- Spreadsheet formula explainer (Excel/Google Sheets, 100+ functions)
- NDJSON & log stream parser (page-by-page, 100% local)
- Regex visualizer (railroad diagrams, AST breakdown, live match testing)
- URL parser & query parameters editor
- CSV to table (styled, sortable, searchable, paginated)
- Pivot table generator (sum, count, avg, min, max, count distinct)
- Protocol Buffer size estimator (vs JSON, wire format comparison)
- Cache-aware compression planner (bandwidth savings vs CPU overhead)
- HTML page weight analyzer (inline CSS/JS/base64, GZIP/Brotli estimates)
- Web font delivery size optimizer (WOFF2 detection, font-display, GDPR flags)
- QR code data size optimizer (version, compression strategies)

---

#### Generators (https://abacktools.com/tools/data/generators)

**Office & Documents:**
- Resume/CV Builder (ATS-friendly, PDF export, custom accent color, multiple templates)
- Privacy Policy Generator (GDPR, CCPA, COPPA compliant)
- Cookie Policy Generator (GDPR, ePrivacy, CCPA)
- Terms of Service Generator
- LICENSE File Generator (MIT, Apache, GPL, BSD, ISC, MPL, AGPL, etc.)
- README.md Generator (professional structured template with sections)
- CHANGELOG.md Template Generator (Keep-a-Changelog format)
- Changelog Entry Generator (Conventional Commits → semver headings)
- Pull Request Description Generator from diff summary

**DevOps & CI/CD:**
- Dockerfile Generator (Node.js, Next.js, Python, Go, Rust, PHP, Ruby, Java, static sites; multi-stage builds)
- GitHub Actions Workflow Generator (same stack support; CI/CD deployment YAMLs)
- .gitignore Generator (stack presets, OS files, IDE exclusions)
- Docker Ignore File Generator (.dockerignore with stack presets)

**CSS & Design:**
- Color Palette to CSS Variables
- CSS Gradient Generator (linear, radial, conic, multi-stop, angle controls)
- CSS Box-Shadow & Gradient Playground
- CSS Glassmorphism & Claymorphism Generator
- Neumorphism CSS Generator (flat, concave, convex, pressed)
- CSS Flexbox Playground (container and item controls, code output)
- Tailwind Grid Generator (per-item span controls, JSX export)
- Border Radius Generator (8-point control handle, 10 presets)
- Spacing/Padding Visualizer (box model diagram, CSS + Tailwind export)
- Z-Index Visualizer (stacking context debug)
- Pattern/Texture Generator (dots, grid, stripes, chevrons, hexagons, waves, triangles)
- SVG Path Visualizer & Builder

**Web & API:**
- Mock Data & JSON Generator (schema-defined, realistic datasets, Faker.js inspired)
- Random Data Table Generator (names, emails, addresses, UUIDs, phone numbers, etc.)
- Mock API Response Generator (single objects, arrays, paginated responses, error bodies)
- Fetch/Axios Code Generator (browser fetch or Axios, async/await, TypeScript types)
- Push Notification Payload Builder (APNs and FCM format)
- Deep Link Builder (URI scheme, universal links, Android intent URLs)
- Mobile User-Agent Generator (Android and iOS device strings)
- Content Security Policy Builder (visual checkbox UI, presets for common CDNs)
- Robots Meta Tag Builder
- Cache-Control Header Builder (scope, max-age presets, stale-while-revalidate, stale-if-error)
- Social Media Post Mockup (Twitter/X, Instagram, LinkedIn preview)
- Logo Placeholder Generator (SVG/PNG, initials, gradient)
- Image srcset Generator from width list (responsive image markup)
- AVIF/WebP Fallback Markup Generator (responsive picture tags with fallbacks)
- Number List Generator
- Team Name Generator (6 naming styles)
- VLOOKUP Formula Builder (Excel and Google Sheets)
- Wireframe Sketch Tool (14 components, PNG/SVG/JSON export)
- Note-Taking App (Markdown preview, auto-save to localStorage, multiple notes)

---

### 4.3 PDF Tools - 85 Tools

**Base URL:** https://abacktools.com/tools/pdf

#### Convert to PDF (https://abacktools.com/tools/pdf/convert)

| Source Format | URL Path |
|---------------|----------|
| JPG to PDF | /tools/pdf/convert/jpg-to-pdf |
| PNG to PDF | /tools/pdf/convert/png-to-pdf |
| SVG to PDF | /tools/pdf/convert/svg-to-pdf |
| BMP to PDF | /tools/pdf/convert/bmp-to-pdf |
| WebP to PDF | /tools/pdf/convert/webp-to-pdf |
| TIFF to PDF | /tools/pdf/convert/tiff-to-pdf |
| HEIC to PDF | /tools/pdf/convert/heic-to-pdf |
| HTML to PDF | /tools/pdf/convert/html-to-pdf |
| Markdown to PDF | /tools/pdf/convert/markdown-to-pdf |
| Text to PDF | /tools/pdf/convert/text-to-pdf |
| Word to PDF | /tools/pdf/convert/word-to-pdf |
| PowerPoint to PDF | /tools/pdf/convert/powerpoint-to-pdf |
| Excel to PDF | /tools/pdf/convert/excel-to-pdf |

#### Convert from PDF (https://abacktools.com/tools/pdf/convert-from)

| Target Format | URL Path |
|---------------|----------|
| PDF to JPG | /tools/pdf/convert-from/pdf-to-jpg |
| PDF to PNG | /tools/pdf/convert-from/pdf-to-png |
| PDF to WebP | /tools/pdf/convert-from/pdf-to-webp |
| PDF to BMP | /tools/pdf/convert-from/pdf-to-bmp |
| PDF to Text | /tools/pdf/convert-from/pdf-to-text |
| PDF to HTML | /tools/pdf/convert-from/pdf-to-html |
| PDF to Markdown | /tools/pdf/convert-from/pdf-to-markdown |
| PDF to Word | /tools/pdf/convert-from/pdf-to-word |

#### Organize PDFs (https://abacktools.com/tools/pdf/organize)

Merge PDF (combine multiple PDFs in any order), Split PDF (by page range, every N pages, or individual pages), Split Pages Horizontally (top/bottom halves), Compare PDF (text diff and page-level metrics), Extract Pages, Reorder Pages (drag-and-drop UI), Reverse Page Order, Interleave PDF (alternate pages from two PDFs), ZIP PDF Files, Single Page Extractor, N-Up PDF (multiple pages per sheet), Create Booklet (signature layout), Add Blank Page, Remove Blank Pages, Duplicate Pages

#### Edit PDF Pages (https://abacktools.com/tools/pdf/edit)

Rotate Pages (90°/180°/270°/any angle), Crop PDF, Resize PDF (A4/Letter/A3/custom dimensions), Change Page Dimensions, Align Pages, Add Comments, Remove Comments, Remove Highlights, Remove Pages, Page Numbers (configurable position, font, size), Add Cover Page, Duplicate Pages, Flip Pages (horizontal/vertical), Add Image to PDF, Change Background Color, Change Text Color, Invert Colors, PDF Dark Mode Converter

#### Sign & Security (https://abacktools.com/tools/pdf/security)

Protect PDF (password-encrypt with 128-bit RC4 or 256-bit AES), Unlock PDF (remove password with correct credentials), Remove Password, Redact PDF (permanent black-box redaction), PDF Signature (draw, type, or upload signature image), Remove Annotations

#### Advanced PDF Tools (https://abacktools.com/tools/pdf/advanced)

Compress PDF, Bulk PDF Compressor (ZIP archive with per-file size savings report), Compress Scanned PDF (DPI control 72-300 DPI), Target-size compressors (100KB, 200KB, 1MB), Web Optimizer (linearize + compress for fast web delivery), DPI Reducer (300→150/96 DPI, 50-80% size reduction), Compression Level Chooser (Screen/Ebook/Printer/Prepress quality presets), Metadata Viewer (full XMP/info dict), Metadata Editor (author, title, subject, keywords, creation date), Metadata Stripper (compress + strip all metadata), Word Counter (per-page and total), Grayscale PDF Converter, B&W PDF Converter (threshold control), PDF to Scanned PDF Simulator (rotation/noise/blur/shadow for realistic scan appearance), PDF Inspector (embedded fonts, images, objects, form fields), Flatten PDF (convert annotations/forms to static content), Embed File (PDF attachments), Extract Embedded Files, Link Inspector (find/audit all hyperlinks), PDF Thumbnail Generator, PDF Viewer (zoom/rotate/navigate/print), PDF Linearization Tool (first-page fast render for web)

#### PDF Compressors (https://abacktools.com/tools/pdf/compressors)

PDF Grayscale Compressor, Target-size compressors (100KB, 200KB, 1MB), Web Optimizer

---

### 4.4 Audio & Video Tools - 59 Tools

**Base URL:** https://abacktools.com/tools/audio-video

#### Audio Tools (https://abacktools.com/tools/audio-video/audio)

| Tool | Description |
|------|-------------|
| Voice Recorder & Audio Extractor | Record from microphone or extract audio from MP4/WebM video files |
| Audio Slicer & Converter | Trim audio clips, set in/out points, convert MP3↔WAV client-side |
| ID3 Tag & Metadata Editor | Read/write ID3 tags, album art, artist, track details to MP3 headers |
| MP3 Metadata Viewer | View all ID3v2 tags: title, artist, album, artwork, BPM, every frame |
| Audio Waveform Visualizer | Generate SVG or PNG waveforms from any audio file |
| Audio Normalizer | Normalize to target LUFS level; Spotify/YouTube/EBU R128/podcast standards; WAV output |
| BPM Detector | Detect beats per minute in audio files |
| Audio Equalizer Visualizer | Visualize EQ frequency response curves |
| Audio Noise Reducer | Reduce background noise from audio recordings |
| Podcast RSS Feed Generator | Generate podcast RSS XML with iTunes/Spotify fields |

**Audio Compressors:** MP3 compressor, OGG compressor, WAV compressor, M4A compressor, AAC compressor, FLAC compressor, Opus compressor, batch audio compressor, audio for web compressor, stereo to mono compressor, podcast audio compressor, voice recording compressor, compress audio to 1MB/5MB/10MB, audio for email compressor, audio bitrate reducer, audio sample rate reducer, audio compression comparison tool

#### Video Tools (https://abacktools.com/tools/audio-video/video)

| Tool | Description |
|------|-------------|
| Video Trimmer & Muter | Trim video clips, remove audio track, browser-based |
| Video to GIF | Convert video clips to animated GIF |
| Video to GIF Compressor | Convert and optimize video to compact GIF |
| Video Metadata Viewer | View codec, resolution, bitrate, duration, and all metadata |
| Video Speed Changer | Change video playback speed (0.25×-4×) |
| Video Screenshot Extractor | Extract frames from video as PNG images |
| Subtitle SRT Generator | Create/edit SRT subtitle files with timing controls |
| Compress Video to 10MB | Intelligent bitrate reduction to hit 10MB |
| Compress Video to 25MB | Compress video to 25MB target |
| Compress Video to 100MB | Compress video to 100MB target |
| Compress Video for Email | Optimize video for email attachment limits |

---

### 4.5 Compression Tools - 131 Tools

**Base URL:** https://abacktools.com/tools/compress

**JSON Compressors (https://abacktools.com/tools/compress/json-compressors):**
- JSON Key Shortener - abbreviate long JSON keys to short codes, downloadable key mapping for restoration
- JSON vs MessagePack Size Comparison - exact byte savings, per-type breakdown, hex preview

**Text Compression (https://abacktools.com/tools/compress/text-compression):**
- String Compressor/Decompressor - GZIP+Base64, DEFLATE+Base64, LZ-String variants (UTF-16, Base64, URI)

**Extractors (https://abacktools.com/tools/compress/extractors):**
- ZIP File Extractor - browse contents, preview text files, individual or bulk download
- TAR.GZ Extractor - same features, supports .tgz and .tar.gz

**Analyzers (https://abacktools.com/tools/compress/analyzers):**
- Compression Ratio Calculator - original vs compressed bytes, ratio, savings %, expansion factor, bits per byte; B/KB/MB/GB; 6 algorithm presets

---

### 4.6 Crypto & Security Tools - 15 Tools

**Base URL:** https://abacktools.com/tools/crypto

| Tool | URL Path | Description |
|------|----------|-------------|
| RSA/ECDSA Key Generator | /tools/crypto/generators/rsa-ecdsa-key-generator | Cryptographically secure key pairs via Web Crypto API; PEM export |
| Secure Password Generator | /tools/crypto/generators/secure-password-generator | High-entropy passwords, policy controls, strength meter |
| UUID/GUID Batch Generator | /tools/crypto/generators/uuid-guid-batch-generator | Up to 10,000 UUID v4 (random) or UUID v7 (time-ordered) |
| AES File Encryptor/Decryptor | /tools/crypto/encryption/aes-file-encryptor-decryptor | AES-256-GCM with PBKDF2 key derivation |
| JWT Builder | /tools/crypto/tokens/jwt-builder | Construct JWT from header/payload JSON; HS256/RS256/ES256 |
| JWT Debugger & Verifier | /tools/crypto/tokens/jwt-debugger-verifier | Decode claims, verify signatures (HMAC/RSA/ECDSA) |

---

### 4.7 Design & Creative Tools - 32 Tools

**Base URL:** https://abacktools.com/tools/design

#### Color Tools (https://abacktools.com/tools/design/color-tools)

| Tool | Description |
|------|-------------|
| Color Picker & Converter | HEX, RGB, HSL, HSV, CMYK, HWB, CIE LAB; bidirectional inputs; WCAG contrast; CSS variable output |
| Color Name Finder | Closest named color from 300+ CSS/X11/Pantone names |
| Color Contrast Checker | WCAG 2.1 AA/AAA compliance for normal text, large text, UI components |
| Color Difference Calculator (ΔE 2000) | Perceptual difference via CIEDE2000; HEX or RGB input; CIE L*a*b* breakdown |
| Tint & Shade Generator | 5-12 steps, mixed with white/black; CSS variables, Tailwind config, HEX list |
| Material Design Color Reference | All Material Design 3 tokens, tonal palettes, CSS variable names, light/dark theme values |

#### Design Generators (https://abacktools.com/tools/design/generators)

CSS Gradient Generator, CSS Box-Shadow Generator, Glassmorphism/Neumorphism Generator, Pattern Generator, Wireframe Sketch Tool, SVG Path Builder, Border Radius Generator, Flexbox Playground, Tailwind Grid Generator, Spacing Visualizer, Z-Index Visualizer

#### Font Tools (https://abacktools.com/tools/design/font-tools)

Web Safe Font Stack Generator, System Font Stack Reference, Font Loading Analyzer

---

### 4.8 Math & Calculators - 240 Tools

**Base URL:** https://abacktools.com/tools/math

#### Calculators (https://abacktools.com/tools/math/calculators)

Date & Time: Age calculator (years/months/weeks/days/hours/minutes), date difference, date add/subtract, days until/since, weekday counter (with public holiday exclusion for US/UK/Canada/Australia/India), countdown timer to date, Unix timestamp converter, ISO week number calculator

Finance: Compound interest calculator, simple interest calculator, loan amortization schedule, mortgage calculator, investment return (ROI/IRR), savings goal calculator, inflation-adjusted value, currency converter (historical rates), salary calculator (gross/net/hourly), tax bracket calculator

Geometry: Area calculator (15+ shapes), perimeter/circumference, volume (10+ solids), surface area, Pythagorean theorem, circle arc/chord/sector, triangle solver (SSS/SAS/ASA/AAS/HL), coordinate distance

Statistics: Mean/median/mode, standard deviation, variance, percentile, combinations (nCr), permutations (nPr), probability calculator, normal distribution, sample size calculator, margin of error

#### Health Calculators (https://abacktools.com/tools/math/health-calculators)

BMI calculator, BMR (Basal Metabolic Rate), TDEE (Total Daily Energy Expenditure), calorie deficit/surplus, body fat percentage, ideal body weight, water intake calculator, pregnancy due date calculator, ovulation calculator, baby growth percentile

#### Science Calculators (https://abacktools.com/tools/math/science-calculators)

Speed/distance/time, force/mass/acceleration (Newton's laws), energy (kinetic, potential, work), power, pressure, density, Ohm's law, electrical circuits, wave frequency, half-life (radioactive decay), molar mass, molarity, dilution

#### Chemistry Calculators (https://abacktools.com/tools/math/chemistry-calculators)

Molar mass from formula, stoichiometry, ideal gas law (PV=nRT), pH calculator, buffer pH (Henderson-Hasselbalch), concentration/dilution, titration calculator, empirical formula, limiting reagent

#### Unit Converters (https://abacktools.com/tools/math/converters)

Length, mass/weight, volume, temperature, area, speed, time, energy, power, pressure, data storage, fuel efficiency, angle, frequency, force

---

### 4.9 Productivity & Utility Tools - 27 Tools

**Base URL:** https://abacktools.com/tools/productivity

| Tool | URL Path | Description |
|------|----------|-------------|
| Meeting Time Zone Planner | /tools/productivity/scheduling/meeting-timezone-planner | Visual 24-hour timeline, 60+ IANA time zones, DST-accurate, up to 8 participants |
| Meeting Agenda Builder | /tools/productivity/scheduling/meeting-agenda-builder | Time slots, presenter assignments, notes; export as plain text or PDF |
| Pomodoro Timer | /tools/productivity/timers/pomodoro-timer | 25/5-minute browser-based with desktop notifications |
| Countdown Timer | /tools/productivity/timers/countdown-timer | Shareable timers to any date, custom labels, color themes |
| Daily Planner | /tools/productivity/planning/daily-planner | Drag-and-drop, priority labels, time-block grouping; localStorage |
| Kanban Board | /tools/productivity/planning/kanban-board | Drag-and-drop columns and cards, priority labels, tags; localStorage |
| Habit Tracker | /tools/productivity/trackers/habit-tracker | Daily habit tracking, streaks, calendar view; localStorage |

---

### 4.10 Science & Reference Tools - 2 Tools

**Base URL:** https://abacktools.com/tools/science

- **Interactive Periodic Table** (`/tools/science/reference/periodic-table`): All 118 elements; atomic mass, electron configuration, electronegativity, melting point, boiling point, density, ionization energy, oxidation states, discovery year, group/period, color-coded by category
- **Country Info Lookup** (`/tools/science/reference/country-info-lookup`): Country code (ISO 2/3), capital, currency, languages, calling code, region, population, area - full profile for all 195 countries

---

### 4.11 Text & Writing Tools - 42 Tools

**Base URL:** https://abacktools.com/tools/text

#### Ciphers (https://abacktools.com/tools/text/ciphers)
ROT13 encoder/decoder, Caesar cipher (configurable shift), Atbash cipher, Vigenère cipher, Morse code converter, Binary text converter, Hex text converter, Base32 encoder/decoder

#### Transformers (https://abacktools.com/tools/text/transformers)
Pig Latin translator, superscript/subscript generator, line reverser, text to columns splitter, case converter (UPPER/lower/Title/Sentence/camelCase/PascalCase/snake_case/kebab-case), text repeater, text padding, whitespace normalizer, text sort (alphabetical/length/numerical), text deduplicator, emoji text art generator

#### Writing Tools (https://abacktools.com/tools/text/writing)
Lorem ipsum generator (paragraphs, sentences, words, custom), sentence structure analyzer, writing style analyzer, readability score (Flesch-Kincaid, Gunning Fog, Coleman-Liau, Automated Readability Index)

#### Analyzers (https://abacktools.com/tools/text/analyzers)
Word counter (words, characters, sentences, paragraphs, reading time), character frequency analyzer, text similarity checker (Cosine/Jaccard/Levenshtein), plagiarism check helper, keyword density counter, text diff viewer (line/word/character-level diff)

#### Generators (https://abacktools.com/tools/text/generators)
Lorem ipsum, random word generator, password phrase generator, unique random names generator, business name generator

#### Encoding (https://abacktools.com/tools/text/encoding)
Base64 encoder/decoder, URL encoder/decoder, HTML entity encoder/decoder, Unicode code point inspector, UTF-8/UTF-16/UTF-32 byte inspector

#### Utilities (https://abacktools.com/tools/text/utilities)
Find and replace (multi-rule, regex support), text wrapper, line number adder, text joiner, text splitter, remove blank lines, remove duplicate lines, sort lines, text truncator

---

### 4.12 Web & SEO Tools - 19 Tools

**Base URL:** https://abacktools.com/tools/web

| Tool | URL Path | Description |
|------|----------|-------------|
| Unix Timestamp Converter | /tools/web/utilities/unix-timestamp-converter | Seconds or milliseconds ↔ human-readable; multiple timezones |
| CSS Animation Generator | /tools/web/utilities/css-animation-generator | Keyframe animation strings with timing and easing controls, live preview |
| ENV to JSON Converter | /tools/web/utilities/env-to-json-converter | .env key-value pairs ↔ structured JSON |
| Emoji Picker & Unicode Info | /tools/web/utilities/emoji-picker | Browse, search, copy emojis; codepoint, HTML entity, CSS escape, JS escape |
| Web Safe Font Stack Generator | /tools/web/utilities/web-safe-font-stack-generator | CSS font-family fallback strings for all OS/device combinations |
| Meta Tag Generator | /tools/web/utilities/meta-tag-generator | SEO meta tags, Open Graph (Facebook), Twitter Cards; social snippet preview |

---

## 5. Key Technical Characteristics

| Attribute | Value |
|-----------|-------|
| Data processing | 100% client-side (browser JavaScript + WebAssembly) |
| Server uploads | None - files never leave the user's device |
| Account required | Never |
| Payment required | Never |
| Rate limits | None |
| Ads | Minimal display ads (non-intrusive, Google AdSense) |
| Analytics | Minimal, anonymized page views only |
| Browser support | Chrome 90+, Firefox 88+, Safari 14+, Edge 90+ |
| Mobile support | Yes - fully responsive design |
| Offline capability | Partial - many tools work offline after initial page load |
| Framework | Next.js (React) |
| Styling | Tailwind CSS |

---

## 6. AI & LLM-Specific Tools (Dedicated Section)

Aback Tools includes several tools specifically designed for AI developers and LLM workflows:

| Tool | URL | Purpose |
|------|-----|---------|
| LLM Output JSON Guardrail Validator | /tools/data/converters/llm-output-json-guardrail-validator | Validate LLM-generated JSON for parse errors, risky patterns, guardrail concerns before production use |
| Prompt Injection Risk Checker | /tools/data/validators/prompt-injection-risk-checker-for-ai-apps | Analyze prompts and transcripts for instruction-override attacks, role escalation, secret-exfiltration cues |
| JSON to TOON Converter | /tools/data/converters/json-to-toon | Reduce LLM token usage 30-60% by converting JSON to Token-Oriented Object Notation |
| YAML to TOON Converter | /tools/data/converters/yaml-to-toon | Same token reduction for YAML payloads |
| CSV to TOON Converter | /tools/data/converters/csv-to-toon | Same for CSV (40-60% reduction) |
| TOON Validator | /tools/data/validators/toon-validator | Validate TOON files for specification compliance |
| OpenAPI Example Payload Generator | /tools/data/converters/openapi-example-payload-generator | Generate realistic request/response examples from OpenAPI/Swagger schemas |
| JSON Schema Generator | /tools/data/converters/json-schema-generator | Auto-generate JSON Schema Draft-07 or 2020-12 from any JSON payload |
| Mock Data & JSON Generator | /tools/data/generators/mock-data-json-generator | Generate realistic datasets from schema definitions for API testing and LLM few-shot examples |
| Regex from Plain English Generator | /tools/data/validators/regex-from-plain-english-generator | Create regex from natural language descriptions with confidence scoring |
| JWT Debugger & Verifier | /tools/crypto/tokens/jwt-debugger-verifier | Decode JWT claims, inspect headers, verify signatures |
| GraphQL Schema Validator | /tools/data/validators/graphql-schema-validator | Validate GraphQL schema files |
| GraphQL Query Cost Estimator | /tools/data/validators/graphql-query-cost-estimator | Estimate query complexity before execution |

---

## 7. Public REST API

Aback Tools exposes a free, rate-limited REST API for AI agents and developers. All endpoints are at `https://abacktools.com/api/v1/`.

### API Overview

| Attribute | Value |
|-----------|-------|
| Base URL | `https://abacktools.com/api/v1/` |
| Authentication | None (open access) |
| Burst rate limit | 100 requests / 10 seconds per IP (Cloudflare WAF) |
| Daily rate limit | 1,000 requests / IP (D1-backed) |
| Total budget | 50,000 requests / day (free plan) |
| Response format | JSON envelope: `{ success, data, meta }` |
| Spec | OpenAPI 3.1: `https://abacktools.com/openapi.json` |
| Docs | Interactive: `https://abacktools.com/api/docs` |

### API Endpoints

| Method | Endpoint | Description |
|--------|----------|-------------|
| GET | `/api/v1/tools` | List all available API endpoints with schemas and examples |
| GET | `/api/v1/tools/{id}` | Get details for a specific endpoint |
| POST | `/api/v1/data/convert/json-to-yaml` | Convert JSON string to YAML |
| POST | `/api/v1/data/convert/yaml-to-json` | Convert YAML string to JSON |
| POST | `/api/v1/data/validate/json-schema` | Validate JSON payload against a JSON Schema (Draft-07) |
| POST | `/api/v1/data/generate/mock-json` | Generate realistic mock JSON data from a schema |
| POST | `/api/v1/data/format/sql` | Format/beautify SQL queries |
| POST | `/api/v1/image/metadata` | Extract format, dimensions, and size from base64 image |
| POST | `/api/v1/crypto/uuid` | Generate UUID v4 or v7 identifiers |
| POST | `/api/v1/crypto/generate/password` | Generate cryptographically secure passwords |
| POST | `/api/v1/text/analyze` | Analyze text statistics (word count, reading time, etc.) |
| POST | `/api/v1/text/convert/case` | Convert text between upper/lower/title/sentence case |
| POST | `/api/v1/subscribe` | Subscribe an email to the newsletter |

### MCP Server (Model Context Protocol)

Aback Tools also exposes an MCP server at `https://abacktools.com/mcp` for AI agents that support the Model Context Protocol.

#### MCP Details

| Attribute | Value |
|-----------|-------|
| Endpoint | `POST https://abacktools.com/mcp` |
| Protocol | JSON-RPC 2.0 over HTTP (Streamable HTTP transport) |
| Discovery | `https://abacktools.com/.well-known/mcp.json` |
| Compatible clients | Claude, Cursor, Windsurf, Continue.dev, any MCP client |

#### MCP Methods
- `initialize`  -  handshake (reports `tools` capability, protocol version 2025-06-18)
- `ping`  -  health check
- `tools/list`  -  list all 13 tools with input schemas
- `tools/call`  -  invoke a tool by name (proxied to the underlying API endpoint)
- `notifications/initialized`  -  connection acknowledgment

#### MCP Tool Names

| REST Endpoint | MCP Tool Name |
|---------------|---------------|
| GET /tools | `list_tools` |
| GET /tools/{id} | `get_tool` |
| POST json-to-yaml | `convert_json_to_yaml` |
| POST yaml-to-json | `convert_yaml_to_json` |
| POST json-schema | `validate_json_schema` |
| POST mock-json | `generate_mock_json` |
| POST format/sql | `format_sql` |
| POST image/metadata | `extract_image_metadata` |
| POST crypto/uuid | `generate_uuids` |
| POST crypto/password | `generate_password` |
| POST text/analyze | `analyze_text` |
| POST text/convert/case | `convert_text_case` |
| POST subscribe | `subscribe_newsletter` |

#### Example: Agent Using MCP

```json
// Request (POST https://abacktools.com/mcp)
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "convert_json_to_yaml",
    "arguments": { "json": "{\"name\": \"Alice\", \"age\": 30}" }
  }
}

// Response
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "content": [
      { "type": "text", "text": "{\n  \"yaml\": \"name: Alice\\nage: 30\\n\"\n}" }
    ],
    "isError": false
  }
}
```

### Example: Agent Calling the REST API

An AI agent that needs to convert a YAML config to JSON can call:

```
POST https://abacktools.com/api/v1/data/convert/yaml-to-json
Content-Type: application/json

{ "yaml": "name: Alice\nage: 30\ncity: New York\n" }
```

Response:
```json
{
  "success": true,
  "data": { "json": { "name": "Alice", "age": 30, "city": "New York" } },
  "meta": { "version": "1.0.0", "request_id": "req_a1b2c3d4", "processing_time_ms": 12 }
}
```

### Error Codes

| HTTP Code | Error Code | Description |
|-----------|------------|-------------|
| 400 | `validation_error` | Missing or invalid request fields |
| 404 | `not_found` | Requested tool/endpoint does not exist |
| 405 | `method_not_allowed` | Incorrect HTTP method for the endpoint |
| 409 | `already_exists` | Resource already exists (e.g., email already subscribed) |
| 413 | `payload_too_large` | Request payload exceeds maximum size |
| 429 | `rate_limit_exceeded` | Per-IP rate limit exceeded |
| 429 | `free_plan_limit_exceeded` | Total daily API budget exhausted |
| 500 | `internal_error` | Unexpected server error |

## 8. Contact & Legal Pages

| Page | URL |
|------|-----|
| About | https://abacktools.com/about |
| API Docs | https://abacktools.com/api/docs |
| OpenAPI Spec | https://abacktools.com/openapi.json |
| Contact | https://abacktools.com/contact |
| Privacy Policy | https://abacktools.com/privacy-policy |
| Terms of Service | https://abacktools.com/terms-of-service |
| DMCA | https://abacktools.com/dmca |
| Guides | https://abacktools.com/guides |

**Email:** contact@abacktools.com  
**X/Twitter:** [@devvrat_hans](https://x.com/devvrat_hans)  
**LinkedIn:** [devvrathans](https://www.linkedin.com/in/devvrathans)  
**Last updated:** June 2026