What makes this diff checker useful
- Word-level highlights — inside a changed line you see exactly which words changed, not just that the line is different.
- JSON-aware — turn on “sort keys” and two JSON files that only differ in key order compare as identical.
- Real patches — the .patch file is a standard unified diff that
git applyandpatchaccept. - Fast and private — it uses the same Myers algorithm as git, runs in your browser and handles tens of thousands of lines. Nothing is uploaded, so it's safe for contracts, configs and code.
Frequently asked questions
Can I compare two files?
Yes — drag a file onto either box or use “Open file…”. Any text format works: code, CSV, Markdown, logs, JSON, XML. Files up to 20 MB.
Can I compare Word or PDF documents?
Copy the text out of each document and paste it. The checker compares plain text, so formatting isn't included.
What does “ignore whitespace” do?
Lines that only differ in spaces, tabs or indentation count as the same — handy after re-formatting code.