Tool Factory

JSON Formatter

Paste JSON to validate and pretty-print it in your browser. Pick your indent, minify, or sort keys, then copy or download. Nothing is uploaded.

  • Validate
  • Pretty-print
  • Minify

Strict JSON validation and pretty-print in this tab. Choose 2 spaces, 4 spaces, or tabs, or minify to one line. Nothing is uploaded.

Paste JSON to validate it, pretty-print it with indentation, then copy or download the result.

A JSON formatter turns a one-line API response or a hand-edited config into readable, indented JSON. Paste it here and every object and array gets its own level of indentation, so you can scan keys, spot missing values, and copy a clean version back into your editor.

The formatter is also a JSON validator. Input is parsed as strict JSON, so trailing commas, single quotes, comments, and unquoted keys are flagged with the parser error and the line and column when your browser provides them. Valid input shows its top-level type, key count, nesting depth, and size in bytes.

Everything stays in this tab, with no upload and no account. Need the data as a spreadsheet? Use the JSON to CSV converter. To read a token payload, open the JWT decoder. Tidy a query with the SQL formatter, make test IDs with the UUID generator, or check JSON-LD with the schema markup validator. More utilities live on the Developer hub.

How to use the JSON formatter

  1. Paste JSON into the box, or load the sample.
  2. Fix anything flagged as Invalid JSON at the reported line and column.
  3. Choose Pretty-print or Minify, your indent, and whether to sort keys.
  4. Copy the result or download it as a .json file.
  5. Clear the box when you are done. Nothing is stored.

Frequently asked questions

What is a JSON formatter?

A JSON formatter takes minified or messy JSON and pretty-prints it with line breaks and indentation so objects, arrays, and nested values are easy to read. This one also validates the JSON and runs entirely in your browser.

Does this JSON formatter validate my JSON?

Yes. The input is parsed as strict JSON before it is formatted. If parsing fails, you see an Invalid JSON message with the parser error and, when the browser reports it, the line and column of the problem.

Is my JSON uploaded to a server?

No. Parsing, formatting, copying, and downloading all happen in this tab. We do not log, store, or send what you paste, so it is safe for API responses and config files you would not post publicly.

Can I choose 2 spaces, 4 spaces, or tabs?

Yes. Pick 2 spaces, 4 spaces, or Tab under Indent. Switch Output to Minify to collapse the JSON onto a single line with no extra whitespace.

Can I sort JSON keys alphabetically?

Yes. Tick Sort keys A–Z to reorder object keys at every level. Array order is never changed, because array order is meaningful in JSON.

Why does my JSON show as invalid?

Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, comments, and values like undefined or NaN. Those are allowed in JavaScript but not in strict JSON. Fix the spot the error points to and the output updates as you type.

Does formatting change my data?

No. Only whitespace changes, plus key order if you turn on sorting. Strings, numbers, booleans, and null keep the same values. Very large integers beyond about 9 quadrillion may lose precision, the same as in any JavaScript JSON parser.

Can I copy or download the formatted JSON?

Yes. Use Copy to put the result on your clipboard, or Download .json to save it as formatted.json. Format replaces the input box with the formatted output, and Clear empties it.

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