Web Tools

Diff Patch Generator

Generate unified diff patches from two text inputs. Configurable context lines, custom file names, downloadable .patch files. Shows added/removed/unchanged line statistics. Runs entirely in your browser — your data never leaves your machine.

diff patch unified compare git text

Published May 30, 2026

All interactive tools run entirely in your browser. Your data never leaves your device.

How It Works

Paste original text in the left panel and modified text in the right panel. The tool computes a unified diff using LCS (Longest Common Subsequence) and outputs a standard unified diff patch that can be applied with git apply or patch.

Features

Unified diff format: standard ---/+++/@@ patch output
Configurable context: 0, 1, 2, 3, 5, or 10 context lines around changes
Custom file names: set the --- a and +++ b header file names
Download .patch: download the generated patch as a file
Copy to clipboard: one-click copy of the patch output
Statistics: lines in A/B, added/removed/unchanged lines, hunk count
Color-coded stats: green for additions, red for removals
5 examples: simple edit, function change, config update, added file, deleted lines
Private: runs entirely in the browser — no data transmitted

Use Cases

Creating patches to share code changes without a full repo
Reviewing text differences in unified diff format
Generating patches for git apply or patch command
Comparing configuration file versions