Text Diff Checker

Paste two versions of a text to see exactly what was added, removed or left unchanged.

FreeNo sign-upRuns in your browserMobile-friendly

Loading tool…

Need help with this tool or found a problem? WhatsApp support Email

What does the Text Diff Checker do?

The diff checker uses the longest-common-subsequence algorithm — the same idea behind tools like Git — to find the smallest set of changes between two texts. Additions are highlighted in green and deletions in red.

Compare by lines for documents, code and lists, or by words to see edits within sentences. Options let you ignore differences in letter case or extra whitespace.

How to use the Text Diff Checker

  1. Paste the original text on the left and the changed text on the right.
  2. Choose line or word comparison.
  3. Optionally ignore case or extra whitespace.
  4. Review the highlighted differences and the summary counts.

Examples

Contract revision

Paste two versions of a clause to see that only “30 days” changed to “15 days”.

Code change

Compare two config files line by line to spot a changed setting.

Common use cases

  • Reviewing document and contract revisions
  • Comparing code or configuration files
  • Checking edits made by a colleague or editor
  • Spotting changes in website copy

Features and benefits

  • Private by design — your data is processed on your device and never uploaded.
  • Free with no account, no watermark and no usage limits.
  • Works on phones, tablets and desktops in any modern browser.

Limitations to know

  • Very large texts (over about 2,000 × 2,000 lines or words) are too big to compare in the browser.
  • This is not a plagiarism checker; it compares only the two texts you provide.

Frequently asked questions

Is my text uploaded?

No. Both texts are compared in your browser.

What does the similarity percentage mean?

It is the share of unchanged lines or words compared with the total, from 0% (completely different) to 100% (identical).

Can it compare Word documents?

Copy the text out of each document and paste it in.

Embed this tool on your website

Add the free Text Diff Checker to your blog or website. Paste the code into your page’s HTML; the tool runs in your visitors’ browsers and stays up to date automatically. Please keep the credit line below the tool.

Free to use on any website. The tool runs inside an iframe served from viptools.pk; nothing your visitors type is sent to your site or ours. Preview the embedded version.

All text tools

Find and Replace Text

Find and replace words or patterns, with case and regex options.

Remove Duplicate Lines

Delete repeated lines from lists while keeping the original order.

JSON Formatter

Beautify JSON with indentation and syntax error locations.

Developer Tools

Text Cleaner

Strip HTML, smart quotes, emojis, line breaks and invisible characters.

Text Reverser

Reverse text by characters, words or lines.

Text Sorter

Sort lines alphabetically, numerically, by length or randomly.