Textarea Diff

Textarea Diff compares two blocks of text line by line and shows what was added, removed, or left unchanged. It uses a Longest Common Subsequence algorithm to produce a minimal, aligned diff, with optional ignoring of whitespace differences and letter case.

1. Paste the original text into the Original textarea and the changed text into the Modified textarea (side by side). 2. Optionally tick Ignore Whitespace to collapse internal whitespace and trim each line before comparing, or Ignore Case to compare lines case-insensitively. 3. Click Compare to run the diff. 4. Review the colored result: green lines with "+ " are additions, red lines with "- " are removals, and plain lines are unchanged. 5. Click Clear to reset both inputs and the result.

The result lists every line in order, classified as added, removed, or unchanged, and color-coded for readability. A summary above the diff reports three counts: added lines (+N), removed lines (-N), and unchanged lines (N). When Ignore Whitespace is on, each line is normalized by collapsing runs of whitespace to a single space and trimming before comparison; when Ignore Case is on, lines are lowercased. These normalizations affect only the comparison, the displayed lines keep their original text.