🔍 Text Diff Checker

Compare two pieces of text and instantly see what changed. Additions highlighted in green, deletions in red. Supports line-by-line and word-level comparison. 100% browser-based — your text never leaves your device.

Developer✓ 100% Free✓ Line & Word Level✓ No Upload
Differences deleted text added text unchanged text
Paste text in both panels to see differences...

How to Use

1
Paste original text

Add your original or older version of text into the left panel.

2
Paste modified text

Add the new or modified version of text into the right panel.

3
Review differences

Additions are highlighted green, deletions red, unchanged text grey. Enable word-level diff for more precise comparison.

Frequently Asked Questions

What is a text diff?
A text diff compares two versions of text and identifies what was added, removed, or changed between them. Lines added in the modified version are shown in green. Lines removed from the original are shown in red. Unchanged lines are shown in grey.
What is word-level diff?
Word-level diff compares individual words within each changed line, highlighting exactly which words were added or removed. This is more precise than line-level diff and useful when comparing paragraphs where only a few words changed per line.
Is this tool useful for code comparison?
Yes. Paste two versions of a code snippet and the diff highlights exactly which lines changed. For full file comparison with git-style output, use git diff or a dedicated code comparison tool. This tool is ideal for quick comparisons of shorter text or code snippets.
Can I compare documents?
Paste the text content of two documents into the panels. The tool compares the text, not the formatting. For Word document comparison, use Microsoft Word's built-in Track Changes or Compare Documents feature, which preserves formatting context.
Is my text sent to a server?
No. The comparison algorithm runs entirely in your browser using JavaScript. Neither piece of text is transmitted to any server.

About This Tool

This text diff tool implements the Myers diff algorithm — the same algorithm used by Git, GNU diff, and most version control systems. It finds the shortest edit script (minimum number of additions and deletions) that transforms the original text into the modified text. The word-level diff applies the same algorithm to individual words within changed lines, providing more granular comparison. Case-insensitive comparison normalises all text to lowercase before comparing, useful when comparing documents where capitalisation may have changed but content is otherwise the same.

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