Text Diff Checker
Compare two texts side by side and highlight the differences.
How to Use This Tool
Compare two pieces of text and instantly see the differences highlighted with color coding. All processing happens in your browser.
- Paste or type the original text in the left panel
- Paste or type the modified text in the right panel
- Click the "Compare" button to see differences
- Added lines appear in green, removed lines appear in red
- Use "Swap" to switch the original and modified texts
- Use "Clear" to reset both text areas
FAQ
What algorithm does this diff checker use?
This tool uses a Longest Common Subsequence (LCS) algorithm to compare lines of text. It identifies which lines are added, removed, or unchanged between the two versions.
Is my data secure?
Yes. All text comparison is done entirely in your browser using client-side JavaScript. Your text is never sent to any server or stored anywhere.
Can I compare large files?
This tool works best with small to medium-sized texts. For very large files (thousands of lines), the comparison may take a moment to process since it runs in your browser.
What do the colors mean?
Green lines with a "+" indicate text that was added in the modified version. Red lines with a "-" indicate text that was removed from the original. White lines are unchanged.