Paste JSON to format, validate, or minify it. Everything runs in your browser — nothing is sent to a server.
Paste any JSON text into the input field. Click Format to pretty-print it with 2-space indentation and syntax highlighting, Minify to produce the smallest valid JSON string, or Validate to check whether your JSON is syntactically correct. The tool uses the browser's built-in JSON.parse() — no data leaves your machine.
A JSON formatter reads raw JSON text and outputs it with consistent indentation so it is readable by humans. It also validates that the input is syntactically correct and displays a clear error message if not.
Paste your JSON into the input field and click Format. The tool indents and colour-codes the output instantly. Everything runs in your browser — nothing is sent to a server.
Minifying removes all whitespace, newlines, and indentation to produce the smallest possible string — useful for APIs and network payloads where file size matters.
Common causes: trailing commas after the last item (not allowed in JSON), single quotes instead of double quotes, unquoted property keys, and undefined or NaN values. The parser error message points to the exact position.
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