Web Tools
Text Diff
Compare two text blocks line-by-line and see additions, removals, and unchanged lines. Supports ignore whitespace, ignore case, and trim options. Unified and side-by-side views. Copy unified diff output. Runs entirely in your browser — your data never leaves your machine.
diff compare text merge changes
Published May 31, 2026
All interactive tools run entirely in your browser. Your data never leaves your device.
How It Works
Paste two text blocks — the original and the modified version. The tool compares them line-by-line using a longest-common-subsequence (LCS) algorithm, highlighting additions, removals, and unchanged lines.
Features
- LCS-based diff: accurate line-by-line comparison
- Unified view: traditional diff output with +/- prefixes and line numbers
- Side-by-side view: original and modified text in parallel columns
- Ignore whitespace: treat lines with different spacing as identical
- Ignore case: case-insensitive comparison
- Trim lines: strip leading/trailing whitespace before comparing
- Diff stats: added, removed, and unchanged line counts
- Copy unified diff: export standard unified diff format
- 5 examples: code change, config update, whitespace, multiline edit, empty comparison
- Private: all computation runs in your browser — no data transmitted
Use Cases
- Comparing two versions of a configuration file
- Reviewing code changes before committing
- Checking text edits in documentation
- Verifying data transformations
- Debugging differences between expected and actual output