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JSON Formatter

Paste any JSON and choose Format to pretty-print it with indentation, Minify to compress it, or Validate to check it. Syntax errors are reported with the exact location. Everything runs locally in your browser.

What this means

JSON is a text format for structured data. Formatting indents nested objects so humans can read them; minifying strips all whitespace so files are smaller; validating checks the text follows the JSON grammar.

How we calculate it

Formula

Format: JSON.parse(text) then JSON.stringify(value, null, 2). Minify: JSON.stringify(value). Validate: JSON.parse succeeds.

Worked example

Paste this and press Format:

  1. 1Paste your JSON into the box.
  2. 2Pick Format, Minify or Validate.
  3. 3The result and any errors appear instantly.

Important assumptions

  • The JSON grammar requires double quotes around keys and strings.

Frequently asked questions

Why is my JSON invalid?

Common causes: single quotes instead of double quotes, a trailing comma, or a missing closing brace. The tool highlights the exact problem.

Can I format large JSON files?

Yes, within reasonable browser memory limits. Huge files over several megabytes may be slow in any tool.

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