100% local comparison

Compare text instantly, locally, and clearly.

Paste two versions, edit in place, format structured text, and review differences without sending your content to a server.

Text Comparison

Live diff workspace

Local Saved settings
Format
Focus
Left text
Right text
No differences

Your text is compared locally in your browser. Nothing is uploaded.

Fast and local

Real-time comparison runs in your browser with no upload step.

Format before review

Clean up JSON, JavaScript, HTML, CSS, Markdown, YAML, and XML before comparing.

Flexible diff modes

Use line, word, or character highlighting for code, prose, hashes, and IDs.

Why it works

A focused compare diff tool for daily review

Compare Diff highlights text changes as you edit. Switch between side-by-side and stacked layouts, ignore whitespace, blank lines, or case, fold unchanged content with context lines, and apply the active change in either direction.

Common uses

  • Compare code snippets, configuration files, JSON payloads, and API responses.
  • Spot checksum or hash differences with character-level precision.
  • Review text while ignoring whitespace, blank lines, or case sensitivity.
  • Format structured data before committing or sharing changes.

Privacy-first architecture

The editor, diff engine, formatter, syntax highlighting, folding, and display settings run entirely in the browser. Your pasted text stays on your device.

Blog

Latest comparison guides

View all

Workflow

How to review text changes without losing context

A practical guide to choosing line, word, and character diff modes for code, prose, hashes, and configuration files.

Read guide

Privacy

Why local text comparison matters

Learn what browser-side diffing means, when it helps, and why sensitive snippets should stay on your own device.

Read guide

Formatting

Format JSON before you compare it

Structured formatting can turn noisy one-line payloads into a reviewable diff before you copy changes back.

Read guide

FAQ

Frequently asked questions

Can I compare JSON and format it before reviewing changes?

Yes. Select JSON, then format the left side, right side, or both sides before reviewing the diff. The same formatter menu also supports JavaScript, TypeScript, HTML, CSS, Markdown, YAML, and XML.

Does Compare Diff upload my text?

No. The comparison workflow runs locally in your browser. Display preferences may be saved in local storage so the editor feels the same the next time you open it.

When should I use character, word, or line mode?

Use line mode for code and documents, word mode for prose, and character mode for short values such as checksums, hashes, IDs, or compact strings.