Text Diff Checker

Compare two text blocks or code snippets to find programmatic differences with this free local diff checker.

Original

Modified

Result

How to use the Text Diff Checker

Paste the original text on the left and the modified text on the right. Click "Compare Lines" to generate a line-by-line diff. Added lines will appear in green, and removed lines will appear in red.

Why do Developers need Diff Tools?

A diff tool is essential for identifying changes between two files or blocks of code. Whether you're comparing API responses, reviewing uncommitted code changes, or finding a typo in a configuration file, a visual diff makes the differences immediately obvious.

100% Client-Side Privacy

Unlike many online diff checkers that send your code to a backend server for comparison, this tool implements the Longest Common Subsequence (LCS) algorithm directly in JavaScript. This guarantees that your proprietary source code or sensitive logs remain strictly on your local machine.