Diff Checker

Diff Checker

The Diff Checker compares two blocks of text and highlights exactly what changed — additions, removals and modifications — line by line. It is ideal for reviewing config edits, copy changes, query tweaks or any before-and-after text.

Why use Diff Checker

  • Side-by-side or unified views of the differences.
  • Highlights added, removed and changed lines clearly.
  • Ignore whitespace and ignore case options.
  • Everything stays in your browser — nothing is uploaded.

How to use Diff Checker

  1. 1Paste both versions. Put the original on the left and the changed text on the right.
  2. 2Pick options. Optionally ignore whitespace or case, and choose side-by-side or unified view.
  3. 3Review changes. Added lines show in green, removed in red; copy the unified diff if needed.

Frequently asked questions

Is my text uploaded anywhere?
No. The comparison runs entirely in your browser; your text never leaves your device.
Can it ignore whitespace or case?
Yes — toggle the options to ignore leading/trailing whitespace or case differences before comparing.
What diff algorithm is used?
A longest-common-subsequence (LCS) line diff, the same approach used by tools like git for clear, minimal changes.

Developer notes

The comparison uses a longest-common-subsequence line diff — the same family of algorithm git uses — which produces minimal, readable change sets rather than noisy character churn.

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