Compare Two Text Files Online

This is the tool people reach for when comparing two versions of the same document — checking what changed between a first and second draft of a contract, an essay, or meeting notes, without reading both side by side line by line. Paste the older version on one side and the newer one on the other, and every insertion and deletion gets highlighted automatically, making it easy to confirm exactly what an editor or collaborator changed.

How to use this text compare tool

  1. Paste the original text on the left.
  2. Paste the changed version on the right.
  3. Differences highlight instantly, line by line and word by word — switch to "Side by Side" for a two-column view.

How does this comparison work?

Lines are matched using a proper diff algorithm (not just position-by-position), so inserting or removing a line doesn't falsely mark everything after it as changed. Within changed lines, the specific words that differ are highlighted more strongly.

Does this detect changes within a line, or only whole lines?

Both — changed lines are shown in full, and the specific words that differ within a changed line are highlighted more strongly, so you can see exactly what changed, not just that the line differs.

Does line order matter?

Not the way you'd expect — this tool matches lines using a real diff algorithm, so inserting or removing a line in the middle no longer marks everything below it as changed.

Is my text sent anywhere?

No — comparison runs entirely in your browser using the jsdiff library, loaded once from a CDN as static code. Neither text box is ever transmitted.