JSON Formatter
Pretty-print messy JSON, find syntax errors fast, or minify it for production. Paste JSON or open a file.
Runs in your browser. Nothing is uploaded Free, no sign-up Works on mobile
Action
Indent
How to use JSON Formatter
- Paste JSON or open a .json file.
- Choose Format or Minify and the indent size.
- Fix any error shown with its line and column, then copy or save the result.
Frequently asked questions
Why is my JSON invalid?
Common causes are trailing commas, single quotes instead of double quotes, unquoted keys and comments. Tick “Fix common mistakes” to repair these automatically.
Can it handle large files?
Yes. Files of several megabytes format in a moment because nothing is uploaded.
Is my data sent to a server?
No. Everything runs in your browser, so API keys, tokens, configs and customer data never leave your machine.
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- JSON to YAML Convert JSON to clean, readable YAML for Kubernetes manifests, Docker Compose, GitHub Actions and config files.
- YAML to JSON Convert YAML config files to JSON, with syntax errors reported with line numbers.