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JSON formatter

Format and validate JSON in your browser.

⌑   Runs on your device

Paste valid JSON. Results update as you type. Up to 1,000,000 characters.

0 characters0 words0 lines
Updates as you type
No uploads. No sign-up.

How to use JSON formatter

  1. Enter json in the input field.
  2. The result updates as you type. Adjust the available settings if needed.
  3. Review the result, then use Copy result or a download link when available.

A clearer view of your JSON

Paste JSON to validate it and choose two spaces, four spaces or a compact result. Copy the output or download a JSON file.

Formatting without executing

Your input is parsed as data. It is never executed as code. Large integers outside JavaScript’s safe range are rejected; quote identifiers that must remain exact.

Working with json formatter

A JSON formatter turns compact structured data into readable indentation or removes optional whitespace for a compact representation. The result must still be valid JSON. Formatting is useful for inspection and debugging, but it does not check a business rule or schema. This preview rejects unsafe numeric values instead of silently presenting a rounded identifier as exact.

A simple example

{"name":"Ada","score":98} → a readable JSON object with your chosen indentation

Common questions

Does this accept comments or trailing commas?

No. This preview parses standard JSON, not JSON5 or JavaScript object literals. Comments and trailing commas produce an error.

Can large numeric IDs lose precision?

Numbers beyond JavaScript’s safe integer range are rejected. Put identifiers that must remain exact in quoted strings before formatting.

Continue your workflow: JSON validator, JSON to CSV, JSON to typescript.