How to use the Text Diff Checker
- Paste the original on the left and the changed text on the right.
- Choose line or word comparison.
- Green = added, red = removed.
About this tool
A diff shows exactly what changed between two versions of a document: config files before and after a deploy, contract drafts, API responses or translated copy. This checker uses a longest-common-subsequence algorithm — the same idea behind git diff — to keep matching content aligned and highlight only real changes.
Line mode is best for code and configuration. Word mode is better for prose, where a single edited word would otherwise mark a whole paragraph as changed.
Tip: to compare two JSON documents reliably, run both through the JSON formatter with Sort keys first so ordering differences disappear.
Frequently asked questions
Is there a size limit?
Very large inputs (millions of comparisons) are refused to keep your browser responsive.
Does it ignore whitespace?
Not yet — use the Text Cleaner to trim lines first.
Is my text uploaded?
No.