Text Compare

How It Works

This text comparison tool analyzes two texts entirely in your browser — no data is sent to any server. Paste your original text on the left and the changed version on the right, then click "Compare" to see all differences highlighted.

Line-by-Line Comparison

The tool uses the Longest Common Subsequence (LCS) algorithm to find the optimal alignment between two texts. This produces accurate diffs even when lines have been moved, added or removed in large blocks.

Color Coding

Red lines indicate removed content (present only in the original). Green lines indicate added content (present only in the changed text). Yellow lines indicate modified content where a line exists in both texts but with differences.

Options

"Ignore case" treats uppercase and lowercase letters as identical. "Trim whitespace" removes leading and trailing spaces before comparing. These options help focus on meaningful content changes.

Privacy First

All processing runs locally in your browser using JavaScript. Your text never leaves your device — there are no server requests, no cookies, and no tracking.

Frequently Asked Questions (FAQ)

Q: How does this text compare tool work?

A: The tool compares two texts line by line and highlights the differences. Green lines indicate additions (text present only in the right panel), red lines indicate deletions (text present only in the left panel), and yellow lines indicate modified content.

Q: Is my text stored on the server?

A: No. All comparison happens directly in your browser using JavaScript. Your text is never sent to any server. Everything stays completely private on your device.

Q: Can I compare code with this tool?

A: Yes! This tool works great for comparing code, configuration files, documents, and any other text content. It preserves whitespace and handles any programming language.

Q: What do the colors mean?

A: Red background means the line was removed (exists only in the original text). Green background means the line was added (exists only in the changed text). Yellow background means the line was modified.

Q: Is there a size limit?

A: Since all processing happens in your browser, there is no server-imposed limit. However, very large texts (over 100,000 lines) may slow down your browser. For typical documents and code files, the tool works instantly.

Q: Does it support different languages?

A: Yes, the tool works with any language and character set, including English, Russian, Ukrainian, Chinese, Arabic, and all Unicode text.

Q: Can I ignore whitespace or case differences?

A: Yes, the tool provides options to ignore case differences and trim trailing whitespace when comparing texts. This is useful when you only care about content changes, not formatting.

Q: Is this tool free?

A: Yes, completely free with no registration required. Use it as many times as you need.