Text Diff Tool
Paste two blocks of text — see line-by-line additions and deletions. Useful for comparing config files, logs, JSON dumps, code, anything line-oriented.
Diff
About this tool
This is a line-by-line diff using the longest-common-subsequence (LCS) algorithm — the same family of algorithm used by git diff, diff -u, and most code editors. It finds the smallest set of insertions and deletions that transforms the left text into the right one.
What it doesn't do
- Word-level or character-level diff: only line-by-line. Two lines that share most words but differ slightly will both be marked changed.
- Three-way merge: only two inputs.
- Patch application: output is for reading, not for piping to
patch. Usegit applywith proper unified-diff headers for that.
Privacy
Everything runs in your browser. The two text blocks never leave the page — no logging, no analytics on the content. Safe for diffing sensitive configs.