Free Text Diff Checker — Compare Two Texts Online
Instantly compare two texts and see exactly what changed. Highlight added and removed words, lines, or characters with a clean side-by-side view — free, private, and runs entirely in your browser.
Word diff, line diff & character diff — all free, all instant.
Paste your original and modified text below, choose a diff mode, and click Compare. Perfect for writers, editors, developers, and anyone who needs to track changes between two versions of a document.
Last updated: May 25 2026
Reviewed by the QuickTooly Team
Text Diff Guide
Why Use a Text Diff Tool?
- Track changes instantly: See exactly what was added, removed, or kept between two versions of any document.
- Three diff modes: Compare by word, line, or individual character depending on how granular you need to go.
- Works for any text: Blog posts, contracts, code snippets, emails, translations — paste any plain text.
- 100% private: Your text never leaves your browser. No server uploads, no data collection.
- Completely free: No account, no paywall, no usage limits.
How the Diff Modes Work
Word Diff
Splits text by whitespace and compares word by word. Best for comparing prose, articles, or any text where sentence-level changes matter. Added words appear highlighted in green; removed words are struck through in red.
Line Diff
Compares text line by line, identical to how tools like git diff work. Best for code, CSV data, configuration files, or any structured text where line boundaries are meaningful.
Character Diff
The most granular mode — compares every single character. Useful for spotting typos, punctuation changes, or invisible whitespace differences that word diff would miss.
Tips for Comparing Text
- Use Line mode for code: Line diff matches how version control systems work and makes structural changes easy to spot.
- Use Word mode for prose: Word diff handles rewrites and edits more naturally than line mode for natural-language text.
- Use Character mode for fine detail: Spot invisible differences like non-breaking spaces, smart quotes vs. straight quotes, or trailing whitespace.
- Comparing JSON? For structured JSON data, try our JSON Compare tool which understands JSON structure and nesting.
Frequently Asked Questions
Is my text stored or sent to a server?
No. All comparison runs locally in your browser using JavaScript. Your text is never transmitted anywhere, stored in a database, or shared with any third party. You can safely paste confidential or sensitive documents.
Which diff mode should I use?
Use Word for general text and writing. Use Line for code, configuration, or structured data. Use Character when you suspect typos or hidden whitespace differences.
Can I compare code with this tool?
Yes — switch to Line mode for the best results with code. It shows exactly which lines were added or removed, matching the behaviour of tools like git diff. For JSON specifically, our JSON Compare tool provides structured, key-by-key comparison.
What do the colours mean?
Red strikethrough in the Original panel shows text that was removed. Green highlighted in the Modified panel shows text that was added. Unchanged text appears without any background colour.
Is there a text length limit?
There is no hard limit — everything runs in your browser. Very large texts (100,000+ characters) may take a second or two to process, but smaller documents compare instantly.