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Sentence Splitter

Split any block of text into one sentence per line instantly. Handles abbreviations (Mr., Dr., U.S.A.), decimal numbers, and ellipsis correctly — no false splits. Three split modes for different text types. Free, private, and no signup required.

Sentence Splitter
Paste or type your text, select a split mode, and the output updates instantly — one sentence per line. Handles abbreviations (Mr., Dr., U.S.A.), decimal numbers, and ellipsis correctly. Upload a text file or paste directly — copy or download the result in one click.

Select Split Mode

Active:Standard SplitSplit on . ! ? — one sentence per line, blank lines removed

Why Use Our Sentence Splitter?

Instant Real-Time Splitting

The sentence splitter updates your output the moment you type — no button to press, no delay. Switch between split modes instantly and see the result immediately.

Smart Abbreviation Handling

Correctly handles abbreviations like Mr., Dr., U.S.A., Jan., and decimal numbers like 3.14 — these are never treated as sentence boundaries, giving you accurate splits every time.

100% Private — No Upload

All sentence splitting happens locally in your browser. Your text never leaves your device. No account, no tracking, no data stored anywhere — safe for confidential content.

Works on Any Device

Use the sentence splitter on desktop, tablet, or mobile — no app to install, no extension required. Upload a text file or paste directly and download the result.

Common Use Cases for Sentence Splitter

NLP & Machine Learning Data Prep

Prepare training data for natural language processing models by splitting paragraphs into individual sentences. One sentence per line is the standard input format for most NLP pipelines and tokenisers.

Content Editing & Proofreading

Split articles, essays, and reports into individual sentences to review each one in isolation. Sentence-by-sentence review catches awkward phrasing, run-on sentences, and structural issues faster.

Language Learning & Flashcards

Split foreign language texts into individual sentences to create flashcard decks or study lists. Each sentence becomes a standalone translation exercise or vocabulary context example.

Translation Workflow Preparation

Split source text into sentences before sending to translators or translation memory tools. Sentence-aligned text is the standard format for CAT tools like SDL Trados and memoQ.

Automated Testing & QA

Split UI copy, error messages, and documentation into individual sentences for automated readability testing, spell-checking pipelines, and content QA workflows.

Text Analysis & Research

Split research papers, legal documents, and reports into sentences for frequency analysis, keyword extraction, and sentence-level sentiment scoring in research workflows.

Understanding Sentence Splitting

What is a Sentence Splitter?

A sentence splitter (also called a sentence tokeniser or sentence boundary detector) divides a block of text into individual sentences, placing each sentence on its own line. This is a fundamental step in natural language processing (NLP), content editing, and translation workflows. The challenge is distinguishing genuine sentence boundaries (a period ending a sentence) from periods used in abbreviations (Mr., Dr., U.S.A.) or decimal numbers (3.14). Our sentence splitter handles all of these cases correctly using pattern-based rules that run entirely in your browser.

How Our Sentence Splitter Works

  1. Input Your Text: Paste any block of text into the input panel, or upload a plain text file (.txt, .md, .csv). The sentence splitter accepts any plain-text content — articles, essays, research papers, or code comments.
  2. Instant Browser-Based Splitting: Select a split mode and the output updates instantly in the right panel. All processing happens locally in your browser — no server, no upload, complete privacy.
  3. Copy or Download: Use the Copy button to copy the split sentences to your clipboard, or Download to save as a .txt file. The stats bar shows the exact number of sentences found.

What the Sentence Splitter Handles

  • Standard Sentence Endings: Splits on periods (.), exclamation marks (!), and question marks (?) followed by a capital letter or quote character.
  • Abbreviations: Protects common abbreviations (Mr., Mrs., Dr., Prof., Jan., Feb., U.S.A., e.g., i.e., etc.) from being treated as sentence boundaries.
  • Decimal Numbers: Protects decimal numbers (3.14, $1.99, 99.9%) from being split at the decimal point.
  • Ellipsis: Treats ellipsis (...) as a single unit rather than three separate sentence endings.

Important Limitations

Rule-based sentence splitting is highly accurate for standard English prose but may produce incorrect splits for: highly informal text with unconventional punctuation, code snippets containing periods in method calls (e.g. object.method()), and languages other than English where sentence boundary conventions differ. For these cases, use the Split on Newlines mode to treat each existing line as a sentence instead.

Frequently Asked Questions About Sentence Splitter

A sentence splitter divides a block of text into individual sentences, placing each sentence on its own line. It is also called a sentence tokeniser or sentence boundary detector. Our sentence splitter processes everything locally in your browser — your text is never sent to a server.

The sentence splitter protects a comprehensive list of common abbreviations — including Mr., Mrs., Dr., Prof., Sr., Jr., Jan., Feb., U.S.A., e.g., i.e., etc. — from being treated as sentence boundaries. These are replaced with placeholders before splitting and restored in the output.

No. The sentence splitter detects digit-period-digit patterns and protects them from being split. Numbers like 3.14, $1.99, and 99.9% are preserved intact in the output.

Standard Split uses punctuation detection (. ! ?) to find sentence boundaries — best for normal prose. Split on Newlines treats each existing line as a sentence — useful for pre-formatted text or bullet lists. Standard + Preserve Paragraphs splits on punctuation but keeps blank lines between original paragraphs, maintaining document structure.

The abbreviation protection list is English-focused, so other languages may produce slightly less accurate results. For non-English text, the Split on Newlines mode is recommended if your text is already line-separated, or Standard Split if it uses standard Latin punctuation.

Yes. Click the Upload button in the input panel to upload any plain text file (.txt, .md, .csv). The file contents will be loaded and split instantly. Download the result using the Download button in the output panel.

Absolutely. All splitting happens entirely in your browser using JavaScript. Your text is never uploaded to any server, stored, or logged. When you close the tab, the text is gone. This makes it safe to use with confidential documents, legal text, or research data.

The output is plain text with one sentence per line, separated by newline characters (\n). This format is directly compatible with most NLP tools, translation memory software, spreadsheet imports, and text processing scripts.

Yes, 100% free with no hidden costs or limitations. No signup required, no premium tier, no usage limits, and no file size restrictions. Use it as many times as you need for any project.