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JSON formatter

Sort your JSON nicely and check its grammar.

Organize JSON, use it like this

Paste the JSON and press Organize to apply indentation. Compressing allows you to remove unnecessary spaces.

Example usage

Property names must be enclosed in double quotes, such as {"name":"Moyoutil","free":true}. A comma after the last item is not allowed.

Please note

Very large integers may have different precision, as they are treated as regular JavaScript numbers. Enter important identifiers as strings.

Step-by-step instructions

  1. Enter JSON data.
  2. Apply indentation with Cleanup or remove unnecessary spaces with Compress.
  3. If an error occurs, check the double quotes, commas, and braces and run again.

Differences between JSON and JavaScript objects

JSON property names and strings must use double quotes. Single quotes, comments, undefined, and a comma after the last item do not conform to JSON grammar. This tool uses JSON.parse and JSON.stringify. Therefore, duplicate keys may result in only the last value remaining, and integers exceeding 2⁵³−1 may result in loss of precision.

JSON cleanup input and result example
inputJudgment
{"ok":true,"count":3}Valid JSON
{'ok':true}Error due to single quote
{"count":3,}Error due to final comma

Frequently Asked Questions

If it passes the grammar check, does it also meet the API specifications?

No. Only JSON grammar is checked. It does not include schema validation such as required fields, data types, or business rules.

Is the notation of the original numbers maintained?

1.0 may be changed to 1 or the notation of large numbers may be different. It is not a tool that preserves the spaces and numbers of the original.

If I paste a sensitive token, will it go to the server?

Tool input is not sent to the server. Still, it's a good idea to make sure you trust shared devices and browser extensions, and avoid using confidential data.

Written and operated by: Moyoutil · Content review: 2026-09-30 · Error report

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