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Original text (before)
Changed text
Diff result
+ 0 added - 0 removed = 0 unchanged
    How to use: Paste the original text on the left and the changed text on the right, and the diff appears below in real time. Green (+) marks added lines, red (-) marks removed lines, and gray (=) marks unchanged lines. Designed for comparisons up to a few hundred lines.
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    Frequently Asked Questions (FAQ)

    What is a text diff?

    A text diff compares two pieces of text to find which parts are the same and which lines were added or removed. It is used to check changes in source code or documents, and it color-codes the shared lines, deleted lines, and added lines.

    Does it compare line by line or character by character?

    This tool compares line by line. It treats each line separated by a line break as the smallest unit, uses the LCS (longest common subsequence) algorithm to find matching lines, and classifies them as unchanged, deleted, or added. It does not highlight character-level differences within a single line.

    Is the text I enter sent to a server?

    No. The diff is computed entirely in JavaScript inside your browser. The text you enter is never sent to or stored on a server, so you can safely compare confidential text.

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