Text Diff Checker

Paste an original and a changed version to see exactly what is different. Compare by lines, words or characters, switch between side-by-side and unified views, and ignore differences in case or whitespace. Added and removed counts are shown, and you can download the changes as a standard .diff file.

How to use the Text Diff Checker

1. Paste the original text on the left and the changed text on the right.
2. Choose to compare by lines, words or characters.
3. Pick side-by-side or unified view for line comparisons.
4. Turn on "Ignore case" or "Ignore whitespace" if those changes do not matter.
5. Copy the result or download a .diff patch file.

Features

• Line, word and character comparison using the Myers diff algorithm
• Side-by-side view with line numbers and word-level highlights on edited lines
• Unified view similar to git diff
• Ignore case and ignore whitespace options
• Added, removed and unchanged counts
• Download a standard unified .diff file

Benefits

• Review edits to contracts, essays and documentation quickly
• Spot small changes such as a single altered number
• Everything runs in your browser — confidential text is never uploaded

Frequently asked questions

Which comparison mode should I use?

Use Lines for code, lists and documents with clear line structure, Words for prose and paragraphs, and Characters to find tiny changes such as typos or changed digits.

What does "Ignore whitespace" do?

Differences in spaces, tabs and indentation are not reported, so reformatted text with the same words shows as unchanged.

Is there a size limit?

Line and word comparisons handle up to 400,000 characters in total. Character comparison is limited to 20,000 characters per text to keep your browser responsive.

What is the .diff file for?

It is the standard unified diff format used by tools like git and patch, so you can share or apply the changes elsewhere.

Related tools

• Character Counter — Count characters with and without spaces, letters, digits and UTF-8 bytes, with live limit bars for X, SMS, titles and meta descriptions.
• Word Counter — Count words, characters, sentences and paragraphs live, with reading time and top keywords.
• Text Sorter — Sort lines alphabetically, naturally by number, by length or in reverse, or shuffle them randomly, with dedupe and case options.
• Case Converter — Convert text to UPPER, lower, Title Case, Sentence case, camelCase, snake_case, kebab-case, CONSTANT_CASE and more.
• Remove Duplicate Lines — Delete repeated lines from a list, with options to ignore case, trim spaces, drop empty lines and keep the first or last copy.
• Sentence Counter — Count sentences and see average sentence length, the longest and shortest sentence, and a numbered list of every sentence.