Format, beautify and validate JSON online

Turn a compact API response or configuration into readable, indented JSON. Validate JSON syntax, spot parsing errors and copy the formatted result. Processing stays in your browser.

Pretty-print JSON with consistent indentation
Validate syntax and report parsing errors
Copy the formatted result

Paste JSON, choose Format & validate, and copy the result. JSON strings and keys need double quotes; comments and trailing commas are not valid JSON.

How to format and check JSON

Paste a JSON object or array into the input area.
Choose Format & validate to indent valid JSON and use Copy output to copy the result.
If parsing fails, correct the syntax and try again. Use double-quoted keys and strings, without trailing commas.

Syntax validation does not check your API contract or a JSON Schema. Formatting also cannot prove that the values in a payload are correct.

Popular ways to use JSON Formatter / Validator

Indent a compact API response so its structure is easier to inspect.
Find a JSON syntax error before using a configuration file.

How processing and privacy work

Processing runs in your browser. The page may download scripts, fonts or processing engines to run the tool; these downloads are separate from uploading your input files.