Text Diff Checker

Compare two blocks of text line by line, with added lines in green, removed lines in red, and a similarity percentage. Great for drafts, code and documents. Free and private in your browser.

Original

Changed

How to use the Text Diff Checker

  1. 1

    Paste your original text on the left.

  2. 2

    Paste the changed version on the right.

  3. 3

    See a line-by-line diff with additions and removals highlighted.

  4. 4

    Check the similarity score and change counts.

Frequently asked questions

How is similarity calculated?

From the longest common subsequence of lines: 2 × common ÷ (total lines in both), shown as a percentage.

Is there a size limit?

It compares up to ~1,500 lines per side to stay fast; larger inputs are truncated.

Is my text private?

Yes — the comparison runs entirely in your browser.

Tips & discussion

Share a trick, ask a question, or help others get more out of this tool.

Log in to share a tip or ask a question.

Loading tips…