JSON Formatter and Validator

Format, validate and minify JSON. Errors show the exact line and column.

Runs in your browser. Your text and files never leave your device.

How to format JSON

  1. Paste JSON from an API response, log file or config into the left box.
  2. Press Format to indent it, or Minify to compress it.
  3. If it is invalid, fix the spot named in the message and press Format again.

Need to send JSON in a URL? Use the URL encoder. Embedding it as text? Try Base64.

Frequently Asked Questions

How do I find the error in invalid JSON?

Paste it and press Format. If the JSON is invalid, the message shows the line and column where parsing failed, and the cursor jumps there.

What are the most common JSON mistakes?

A comma after the last item, single quotes instead of double quotes, keys without quotes, and comments. JSON allows none of these, even though JavaScript does.

What does Minify do?

It removes all spaces and line breaks outside strings, giving the smallest valid JSON for APIs and storage.

Is my JSON sent to a server?

No. It is parsed and formatted in your browser, so API keys and private data inside it stay on your device.

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