JSON Formatter

What this tool does

Use this JSON formatter to turn compact or unevenly indented data into a readable two-space layout. You can also minify valid JSON to one line or run a syntax check on its own. Invalid input shows the message returned by your browser's JSON parser, and no pasted content leaves the browser tab.

How to use it

1. Paste or type the JSON you want to process.
2. Choose Format for two-space pretty printing, Minify for one-line output, or Validate for a syntax check.
3. Review the result and copy it when ready.

Privacy

This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.

Frequently asked questions

What do JSON formatting and pretty printing do?

They add line breaks and indentation to valid JSON so nested objects and arrays are easier to read. They do not convert the data to another format.

Does formatting or minifying JSON change the data?

The tool parses valid JSON and serializes it again. Formatting adds whitespace and minifying removes unnecessary whitespace, while the parsed data values keep the same meaning.

Why are trailing commas, single quotes or unquoted keys invalid?

Strict JSON requires double quotes around keys and strings and does not allow a trailing comma after the final member. This tool reports the syntax error instead of repairing it.

Is syntax validation the same as JSON Schema validation?

No. Syntax validation checks whether the text can be parsed as JSON. JSON Schema validation also checks fields, types and structural rules. This tool performs syntax validation only.

Is my JSON uploaded or stored?

No. Formatting, minifying and validation run in your browser tab, so your JSON and the generated result are not uploaded to LocalTools.