Text Diff Viewer - Compare Two Text Files

Compare text files side-by-side or in unified format. Highlight additions, deletions, and changes. Perfect for code review and document comparison.

Original Text (Left)

Modified Text (Right)

Unified Side-by-Side

Ignore whitespace

Enter text in both fields and click "Compare"

Related Tools

ANSI Art Viewer - BBS Text Art Display

Log File Viewer - Search, Filter & Highl…

NFO Viewer Online - Scene Release Info R…

View all Text viewers →

Frequently Asked Questions

A diff shows differences between two versions of text. Lines added, removed, or modified are highlighted with colors and markers (+/-), making it easy to see what changed.

Unified view shows both texts in a single column with +/- markers. Side-by-side view displays texts in parallel columns for easier comparison of corresponding lines.

Yes. Perfect for comparing code before/after refactoring, reviewing pull request changes, or checking configuration file differences. Supports any plain text format.

Yes. Enable 'Ignore whitespace' to skip differences in spaces, tabs, and line endings. Useful when comparing formatted code or indentation changes.

No. All comparison happens in your browser using JavaScript. Your text files never leave your device.

Yes. Export as unified diff format (standard .diff/.patch file) compatible with git, patch, and other diff tools.

The viewer uses the Myers diff algorithm, the same algorithm used by git diff. It finds the minimal set of changes between the two texts.

Yes. Use the 'Swap' button to reverse which text is considered original vs modified. This changes what appears as additions vs deletions.

Yes, but very large files (>5MB) may be slow. The diff algorithm performance depends on the number of differences, not just file size.

This viewer compares line-by-line, which is standard for text diff tools. Character-level diffs within lines are highlighted when lines are modified.