Format JSON Online

Paste JSON, choose Format to read its structure or Minify to make it one line. The tool checks syntax when you run either action and lets you copy the result.

Format or minify JSON

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Output
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How to format JSON in 3 steps

01

Paste the JSON input

Paste a JSON string into the input. Syntax is checked when you select Format or Minify.

Choose the action for your task

You needActionCheck the result
Read an API response or configPaste JSON and select Format. The tool uses two-space indentation and colors values.Review keys, arrays and values before copying.
Get a compact JSON stringSelect Minify. Whitespace outside strings is removed; whitespace inside string values remains.Compare Input and Output sizes; the result is not always smaller than the input.
Check JSON syntaxRun Format or Minify. Both parse the JSON before producing output.If parsing fails, read the browser error, correct the input and run it again.

If JSON does not produce the expected result

Syntax error
Check for trailing commas, comments, quoted property names and matching brackets. The tool accepts standard JSON and does not repair invalid input.
Numbers or key order look different
The tool rebuilds text with JavaScript JSON.parse and JSON.stringify. For very large integer IDs or systems that need the original representation, compare with the source and use a suitable parser before relying on the output.
Large input slows the page
Parsing and highlighting happen in the browser tab. Split the input or use a local tool suited to large files.

Where is your JSON processed?

Format and Minify run in the browser tab; this tool does not send pasted JSON to an KitoTool JSON processing API. Clear removes the input and result from the interface. Follow your organization’s policy when handling sensitive data.

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