Does this tool upload my text anywhere?

No. The comparison runs entirely in your browser using a diff algorithm implemented in JavaScript — nothing is sent to a server.

What is the difference between line and word diffing?

Line diffing treats each line as a unit, so it is ideal for code or logs. Word diffing highlights individual changed words within a line, which is clearer for prose edits.

Can I ignore formatting differences like extra spaces?

Yes. Advanced options let you ignore case, leading/trailing whitespace, blank lines, punctuation, accents and line-ending differences independently.

What is a unified diff / patch file?

It is the standard `.diff` format used by tools like git and patch, showing changed hunks with a few lines of surrounding context. You can export it directly.

Can I merge the two versions?

Yes, in the block view you can pick left or right for each changed block to build a merged result, then copy or download it.

ToolMano

Text diff checker

Compare two texts and see exactly what changed.

No uploadNo signupWorks offline

Original text

Drop files here or click to choose

Load left side from file

Up to 20 MB

Changed text

Drop files here or click to choose

Load right side from file

Up to 20 MB

Quick presets

Granularity

View

Ignore caseIgnore whitespace

Paste text on both sides to see a comparison.

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About text diff checker

Text diff checker compares two blocks of text and highlights every addition, deletion and change between them. Choose character, word, line or sentence granularity and view the result side-by-side, inline, or as a unified patch you can save as a .diff file.

Everything runs locally with a custom LCS-based diff algorithm — nothing is uploaded. It is built for comparing contracts, code snippets, config files or article drafts, with ignore rules for case, whitespace, punctuation and more so you only see the changes that actually matter.

Extra tools like line sorting, duplicate/unique extraction and a similarity score make it useful beyond simple comparisons — for cleaning up lists or checking how much two versions of a document diverge.

How to use Text diff checker

1Paste or upload the original text on the left and the changed text on the right.
2Pick a comparison granularity and view mode.
3Tune ignore rules (case, whitespace, punctuation, etc.) in Advanced.
4Review the highlighted differences and statistics.
5Copy the merged result or export a unified diff / HTML report.

What it does

Character, word, line and sentence-level diffing
Side-by-side, inline and unified patch views
Ignore case, whitespace, punctuation, accents, HTML tags and line endings
Similarity percentage with added/removed/changed/unchanged counts
Sort lines and extract unique or duplicate lines before comparing
Adjustable context lines for unified diffs
Swap sides and load either side from a file
Export as .diff patch or a standalone HTML report
Per-block merge: keep left, right, or both
Line numbers and word-wrap toggle

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Also searched as

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