Text Difference Checker
Compare two text blocks and instantly highlight what changed — additions, deletions, and moved text. Choose word, line, or character comparison.
What is a Text Difference Checker?
A Text Difference Checker, also called a diff tool, is an online utility that lets you compare two blocks of text side-by-side and instantly highlight the differences. Whether you’re reviewing code changes, editing documents, checking for plagiarism, or verifying content revisions, this tool makes it quick and easy to spot modifications.
Our free online text comparison tool works in your browser, so your content never leaves your device. It can compare text word-by-word, line-by-line, or even character-by-character for precise change detection. Changes are color-coded: insertions in green, deletions in red, so you can see exactly what has been added, removed, or altered.
This difference finder is ideal for developers, writers, editors, and anyone who needs to detect even the smallest text change in a document, configuration file, or block of code. It works equally well on mobile, tablet, and desktop devices.
Key Features
- Compare by words, lines, or individual characters
- Highlight changes with clear color coding (green for additions, red for deletions)
- Swap texts, clear inputs, and copy results with one click
- Export results as HTML for sharing or documentation
- Runs entirely in the browser for maximum privacy — no data sent to servers
- Responsive, mobile-friendly interface for use anywhere
How to Use
- Paste the original text into the left box (A).
- Paste the modified text into the right box (B).
- Select the comparison mode: words, lines, or characters.
- Click Compare to view highlighted differences instantly.
- Optional: Use Export as HTML to save or share results.
Popular Uses
- Code review and source file comparison
- Editing and proofreading written content
- Detecting plagiarism or unauthorized content changes
- Tracking revisions in contracts or legal documents
- Spotting changes in configuration or data files
Frequently Asked Questions
Is my text stored on the server?
No. All text comparison is processed locally in your browser. Your content never leaves your device, ensuring complete privacy.
Which comparison mode should I choose?
Use Words for natural language text such as articles or emails, Lines for code or structured lists, and Characters for very detailed comparisons where every symbol matters.
Can I use this tool for code comparison?
Yes. This tool works perfectly as an online code comparison tool or side-by-side diff viewer for developers.