Network Tools

Check DMARC records for any domain via Cloudflare DNS-over-HTTPS. Validate email authentication policy (none/quarantine/reject), analyse alignment settings (adkim, aspf), and extract reporting addresses (rua, ruf) - free online DMARC record checker.

Check if DNS queries and WebRTC are leaking your real IP outside your VPN tunnel. Detects local IPs via WebRTC STUN requests, checks public IP and geolocation via free APIs, and identifies DNS resolvers - free online DNS leak test.

Compare DNS records across Cloudflare, Google, and Quad9 nameservers automatically. Detects differences in A, MX, NS, CNAME, TXT, AAAA, and SOA records with severity indicators - free online DNS comparison tool.

Look up PTR records for any IPv4 or IPv6 address via Cloudflare DNS-over-HTTPS. Instantly find the hostname behind any IP address with DNSSEC validation status and query time - free online reverse DNS lookup tool.

Paste any Set-Cookie header value and analyze its security configuration against best practices. Validates Secure flag, HttpOnly flag, SameSite policy (Strict/Lax/None), Expires/Max-Age validity, Path and Domain scope. Get a 0-100 security score per cookie with specific warnings and actionable recommendations - free online cookie security checker.

Look up A records for up to 50 domains at once via Cloudflare DNS-over-HTTPS. Sortable results table with IP addresses, response times, TTL, DNSSEC validation status, error detection, and CSV export - free online bulk DNS lookup tool.

Test if your real IP address is leaking through WebRTC while using a VPN or proxy. Detects local IP addresses via WebRTC ICE candidates from RTCPeerConnection and compares them against your public IP via ipify.org. IP classification (private, loopback, public) with pass/fail verdict, IP type badges, and remediation steps for fixing leaks - free online WebRTC leak test.

Fetch any URL and inspect all HTTP response headers with plain-English descriptions. Check status codes, security headers (HSTS, CSP, X-Frame-Options), caching rules, CORS policies, and content negotiation - free online HTTP header checker.

Trace the full redirect chain for any URL. Follow every 301, 302, 307, and 308 redirect hop-by-hop with per-hop timing and Location header inspection. Detect redirect loops automatically with clear reporting - free online HTTP Redirect Chain Checker.

Check if TLS certificates for any domain appear in Certificate Transparency logs via crt.sh. View issuer details, validity dates, SHA-256 fingerprints, Subject Alternative Names (SANs), and CT log names - free online CT log checker.

Validate SPF records for any domain via DNS-over-HTTPS TXT lookup. Checks SPF syntax, DNS lookup limits (max 10), and common misconfigurations like missing -all policy, duplicate includes, and invalid IP addresses - free online SPF record checker.

Test if any URL is reachable and measure its fetch timing using the browser Performance API. Shows DNS resolution, TCP handshake, TLS handshake, TTFB, and total load time with an interactive waterfall chart - free online HTTP connectivity test.

Check if a domain is in the Chrome/Chromium HSTS preload list via the official hstspreload.org API v2. Shows preload status (Preloaded, Pending, Rejected, Not Preloaded), includeSubDomains coverage, bulk submission info, and query time with detailed explanations - free online HSTS preload checker.

Convert any IPv4 address to dotted-decimal, hexadecimal, packed hex, binary, packed binary (32-bit), decimal integer, and IPv6-mapped formats instantly. Smart input detection supports dotted-decimal, decimal integer, packed hex, and packed binary input with real-time conversion, IP class detection, and special address identification (private, loopback, link-local, multicast) - free online IP address converter.

Paste any Cache-Control header value and get a detailed analysis of every directive (max-age, public, private, no-cache, no-store, stale-while-revalidate, immutable, and more). Understand caching behavior, revalidation rules, and CDN implications with optimization recommendations - free online Cache-Control header analyzer.

Build cURL commands visually with our interactive cURL command generator. Select HTTP method (GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS), enter URL, add custom headers, set request body in JSON/form/raw format, configure authentication (Basic, Bearer, Digest), and toggle advanced options (follow redirects, verbose, insecure, timeout). Multi-line and single-line output with copy-to-clipboard - free online cURL command generator.

Send CORS preflight (OPTIONS) requests to any URL with custom origin, method, and headers. Analyzes 6 Access-Control-* response headers (Allow-Origin, Allow-Methods, Allow-Headers, Allow-Credentials, Max-Age, Expose-Headers) with pass/fail checks and detailed explanations. Proxy mode bypasses browser restrictions to see raw server response headers - free online CORS preflight tester.

Paste CORS response headers and validate them against the CORS specification. Checks Access-Control-Allow-Origin, Allow-Methods, Allow-Headers, Allow-Credentials, Max-Age, Expose-Headers, and Vary with severity-based pass/fail analysis. Optionally verify against expected origin, method, and custom headers - free online CORS header validator.

Check the Vary HTTP header to understand caching behavior. Enter any Vary header value and see detailed analysis of how each header affects cache efficiency, with cache efficiency, performance, and security ratings. Detects Vary: *, missing Vary: Origin with CORS, User-Agent cache fragmentation, Cookie header issues, and more - free online Vary header checker.

Convert subnet masks to wildcard masks (inverse masks) used in Cisco ACLs and routing protocols. Enter any dotted-decimal subnet mask or wildcard mask for instant bidirectional conversion with binary representation, CIDR notation, host counts, and subnet class analysis - free online Wildcard Mask Calculator.

Check if a website sets the X-Frame-Options header for clickjacking protection. Enter a URL for a live header check via HEAD request, or paste a header value (DENY, SAMEORIGIN, ALLOW-FROM) for detailed security analysis with browser support information and recommendations - free online X-Frame-Options checker.

Look up geolocation for up to 20 IP addresses at once via ip-api.com batch API. Get country, city, ISP, coordinates, timezone, and AS number for each IP in a sortable table with CSV export - free online bulk IP lookup tool.

Check the Referrer-Policy header for any URL. Detects the policy (strict-origin-when-cross-origin, no-referrer, same-origin, etc.) and explains what referrer info is sent for same-origin, cross-origin, and protocol downgrade requests with security ratings - free online Referrer-Policy checker.

Given a start and end IPv4 address, find the most specific CIDR notation that covers the range. Converts any IP range to the minimal set of non-overlapping CIDR blocks with full subnet details: network address, subnet mask, wildcard mask, broadcast address, first/last usable IPs, and host counts - free online IP to CIDR calculator.

Browse and search OAuth 2.0 scopes across top providers: Google, Microsoft, GitHub, Slack, and Facebook. Filter by provider, search by scope name or description, and see detailed scope information including documentation links - free online OAuth scopes reference.

Parse any URL into its components: protocol, hostname, port, path, query parameters, and fragment. Shows both raw (encoded) and decoded values side by side with query parameter breakdowns, URL validation warnings, and copy-to-clipboard - free online URL parser.

Convert text and files to data URIs (data:[MIME-type];base64,...) instantly. Type or paste text, upload files, or drag and drop to convert. Auto-detects MIME types from over 60 file extensions and 10+ text content patterns (HTML, JSON, SVG, CSS, JavaScript, Markdown, YAML). Size analysis with overhead percentages, optimization recommendations, and one-click copy - free online Data URI Generator.

Build, encode, and decode URL query strings from key-value pairs. Add parameters in an interactive table with automatic URL-encoding, choose from Standard, Form URL-encoded, or Minimal encoding modes, load presets for UTM campaigns and API pagination, and copy the result with or without the leading ? - free online query string builder.