Text Difference: instructions, examples and limits

What it does

Uses a longest-common-subsequence line comparison. “+” marks additions; “−” marks removals.

Use Text Difference to review two plain-text versions and see which lines were added, removed or kept.

How to use it

1. 1

   Paste the earlier version into the first panel and the later version into the second.

2. 2

   Read the line-level result and check the surrounding context before accepting a change.

3. 3

   Copy the final version from your own editor; the diff is a review aid, not a merge engine.

How the result is produced

Uses a longest-common-subsequence line comparison. “+” marks additions; “−” marks removals.

Important limits

Maximum 250,000 line-pair comparisons. This compares text, not semantic meaning.

Checks before sharing or relying on the result

• The comparison is line-based, so a changed line is shown as a change rather than a character-by-character patch.
• Large inputs are bounded to keep the browser responsive.
• Whitespace and line-ending differences can be meaningful; do not normalise them without deciding that they are noise.

Choosing the next step

Pick the narrowest operation that matches the problem. A line tool preserves line boundaries, while a text-wide transform may change punctuation or spacing. For sensitive text, use the browser-local workflow and avoid putting the input into a share URL.