Text Diff Checker

Compare two texts and highlight what was added, removed or changed.

OfficeBuild an invoiceFill, preview, and download a clean invoice PDF in minutes.Open

Added text is shown in green, removed text struck through in red, and unchanged text in your normal colour. Choose by-line for a paragraph or document compare, or by-word for sentence-level edits. The comparison uses a longest-common-subsequence diff and runs entirely in your browser.

How to compare two texts

Paste the original on the left and the changed version on the right. Choose by-line or by-word, and the differences appear below — green for additions, struck-through red for deletions. A running count shows how many tokens were added and removed.

When a diff helps

Spot what an editor changed in a draft, review an edit to a contract, compare two versions of a config file, or check that a copy-paste didn't drop a line. Because it's live, you can tweak either side and watch the diff update.

Questions

How does the comparison work?
The tool uses a longest-common-subsequence diff — the same approach version-control tools use — to find the smallest set of additions and deletions that turns the first text into the second. Added text is shown in green, removed text struck through in red.
Should I compare by line or by word?
Use by-line for documents and code where whole lines change, and by-word for prose where you want to catch a single edited word inside an otherwise identical sentence.
Is my text uploaded anywhere?
No. Both texts are compared in your browser as you type or paste. Nothing is sent to a server, so it's safe for drafts, contracts or private notes.