JSON Formatter & Validator

Paste JSON to check whether it parses correctly, format valid data with indentation, or minify it into a compact representation. The tool is useful for API responses, webhooks, configuration files, browser storage, and debugging copied payloads. Formatting can reveal structure, but it cannot repair an invalid object automatically; parser errors usually point you toward missing quotes, commas, braces, brackets, or non-JSON values.

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Format and validate JSON in your browser

Paste JSON to check whether it can be parsed, then pretty-print it for readability or minify it for compact storage and transmission. The tool is useful when an API response, configuration file, webhook payload, or copied code is difficult to read.

What valid JSON looks like

JSON uses objects in braces, arrays in brackets, double-quoted property names and strings, and a limited set of value types. A simple object looks like:

{
  "name": "Probably Useful",
  "active": true,
  "tools": 19
}

Common reasons JSON fails validation

• Using single quotes instead of double quotes around strings.
• Leaving a trailing comma after the last property or array item.
• Forgetting a comma between properties.
• Using an unquoted property name.
• Pasting JavaScript syntax such as comments or undefined, which are not valid JSON values.

Pretty-printing vs minifying

Pretty-printing adds indentation and line breaks so humans can scan the structure. Minifying removes unnecessary whitespace so the same data takes fewer characters. Neither operation changes the underlying values.

Privacy

The formatter uses browser-side parsing. Even so, avoid pasting production secrets, access tokens, personal information, or credentials into any tool unless you are comfortable with the environment you are using.

Frequently asked questions

Is JSON the same as JavaScript?

No. JSON was inspired by JavaScript object notation but has stricter syntax and is language-independent as a data format.

Can formatting repair invalid JSON automatically?

No. The tool can identify that parsing failed, but ambiguous mistakes still require you to correct the source.