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Text Diff

Paste two pieces of text or code and highlight the differences word-, line-, or character-by-character. Great for comparing ChatGPT vs Claude output, or diffing two content drafts.

All tools Browser-only

Text A (original)

Text B (new)

Mode: By word By line By character Ignore case Ignore whitespace

Differences

In B but not in A (added) In A but not in B (removed)

Added

Removed

Unchanged

Enter text in both boxes above to compare

When to use this

Compare AI outputs: paste output from two models (ChatGPT vs Claude vs Gemini) and see where they differ — which one is more concise, which adds extra fluff.
Diff content drafts: v1 vs v2 of an article, see what an editor changed.
Simple code diff: short code snippets — verify a bug fix or refactor.
Verify translations: paste original + back-translation, spot meaning loss.

3 diff modes

By word (default): best for prose and natural language.
By line: like git diff — for code or config files.
By character: maximum detail — catches typos and punctuation changes.

Who this is for

Fullstack/backend/devops engineers — debug JWT, format JSON/SQL, parse cURL, compute CIDR subnets, draft Mermaid diagrams, write conventional commits… Daily toolkit alongside your terminal and editor.

FAQ

Is my pasted code/token sent anywhere?

No. All TopDev dev tools run 100% client-side — JWT, SQL, JSON, cURL, regex… process in-browser. Disconnect to verify. Safe for internal tokens, production DB queries, API keys.

Does it work offline / install as a PWA?

Tools work offline after the first load. Installable PWA is on the roadmap — for now you can bookmark and use without internet.

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