JSON Formatter & Validator
Pretty-print, minify, and validate JSON instantly
So funktioniert's
- 1Paste your JSON
Drop or paste any JSON string into the input box. Even messy, minified JSON works.
- 2Choose format or minify
Pretty-print with 2 or 4 spaces, or collapse to a single line for embedding.
- 3Copy or download
Copy formatted JSON to your clipboard or download it as a .json file.
Über JSON Formatter & Validator
Free online JSON formatter, beautifier, and validator. Paste any JSON to instantly pretty-print with 2 or 4-space indentation, minify to a single line, or catch syntax errors. Runs entirely in your browser - your data never leaves your device. JSON Formatter & Validator auf 712 Tools läuft komplett in deinem Browser über native JavaScript APIs - kein Server sieht je deine Daten. Das heißt: sofortige Ergebnisse, volle Privatsphäre und keine Upload-Limits.
Ob für eine Debugging-Session, einen schnellen Sanity Check oder einen Produktions-Incident - dieses Tool ist kostenlos so oft nutzbar, wie du willst. Keine Wasserzeichen, kein Signup und keine Ads im Tool selbst.
Häufige Fragen
Is my JSON uploaded anywhere?
No. All parsing and formatting happens in your browser using the native JSON parser. Nothing is sent to a server.
What does the validator catch?
Missing commas, unquoted keys, trailing commas, mismatched brackets, and any invalid JSON per the RFC 8259 spec.
Can it handle large files?
Yes, up to your browser's memory limit. Files over ~50 MB may slow down the pretty-printer but validation stays fast.
Does it support JSON5 or JSONC?
Not yet. Only strict JSON (no comments, no trailing commas, keys must be double-quoted) is supported.
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