Line-by-line alignment
A longest-common-subsequence engine lines up the two versions so additions, deletions and edits land exactly where they belong.
Compare · Side-by-side · Inline · Word & character · No upload
Text Diff Checker
Paste two versions of any text and see exactly what changed. The tool aligns the two blocks line by line, highlights added, removed and modified lines, and can drill down to the precise words or characters that differ. Switch between a side-by-side view and a compact inline view, ignore case or whitespace, and export a standard unified diff. Everything runs in your browser — nothing is uploaded.
Original text
Changed text
Differences
Paste text in both panes to see the differences.
Ready
Key features
Word & character highlight
Changed lines show the precise words or characters that differ, so a one-letter typo doesn't flag the whole paragraph.
Whitespace & case control
Ignore letter case, collapse all whitespace, trim trailing spaces and skip blank lines to surface only meaningful changes.
Unified diff export
Copy or download a standard @@ hunk diff you can paste into a patch, a pull request or a code review.
Frequently asked questions
How do I compare two blocks of text?
Paste the original on the left and the changed version on the right. With Live on, the comparison updates as you type; otherwise press Compare. Removed content is shown in red, added content in green.
What is the difference between Word and Character granularity?
Both still align the text line by line. Word highlights which whole words changed inside an edited line, which reads naturally for prose. Character marks individual characters, which is handy for spotting a single typo, a changed digit or a moved bracket. Line only skips intra-line highlighting entirely.
Can I ignore formatting differences?
Yes. Tick Case to treat upper and lower case as equal, All whitespace to ignore spaces and tabs completely, Trailing spaces to drop end-of-line whitespace, and Blank lines to skip empty lines. The original text is always displayed unchanged — only the comparison is affected.
What does the unified diff export contain?
It produces the same format git diff and diff -u use: grouped hunks with @@ -a,b +c,d @@ headers, three lines of context, and -/+ prefixes. You can paste it straight into a patch file or a review comment.
Is my text sent to a server?
No. The whole comparison runs locally in your browser with JavaScript. Nothing is uploaded, so it is safe for private documents, contracts and source code, and it keeps working offline once loaded.