Diff Checker

Compare two text blocks side by side in your browser. Highlight additions and deletions — no upload, free online diff checker.

Compare text locally without a cloud diff

See what changed between two versions of a config, contract clause, or log excerpt. Nothing is sent to a server — useful for confidential drafts.

What you can do with it

Review config changes
Paste old and new environment snippets before deploying.
Spot edits in pasted content
Compare two email drafts or policy paragraphs without leaving sensitive text on a diff SaaS.

How to compare text

  1. Paste the original text on the left.
  2. Paste the revised text on the right.
  3. Review highlighted additions and deletions.

Side-by-side diff without a paste site

Legal clauses, HR policies, and production configs are poor candidates for cloud diff tools. Comparing locally highlights line changes while both versions stay on your device.

Line diff vs semantic merge

This tool shows textual additions and removals. For structured JSON, format both sides with JSON Formatter first so diffs align on pretty-printed lines.

Related reading and tools

Frequently asked questions

Is my text uploaded?
No. Diffing runs entirely in your browser. Both sides stay on your device.
What diff style is used?
Line-based comparison with highlighted added and removed lines.
Can I diff configs or code?
Yes. Paste any plain text — JSON, YAML, logs, or source snippets.

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