JSON Formatter

The JSON Formatter takes any JSON string — valid, minified, or broken — and instantly pretty-prints it with configurable indentation, inline error reporting, and one-click minify. Unlike most online formatters, every byte of your data stays in your browser: nothing is uploaded, logged, or sent to a server, which makes this tool safe for pasting API keys, JWT payloads, config files, and production data. Paste malformed JSON and you’ll get the exact line and column of the first syntax error (trailing comma, unquoted key, single quotes, mismatched brackets) so you can fix it in seconds instead of staring at a 5,000-line file.

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   Paste your JSON into the input box at the top. You can also drag a .json file onto the page or press Ctrl/Cmd+V anywhere.

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   The formatted result appears instantly below. Use the indent selector (2 spaces, 4 spaces, or tab) to match your project’s style guide.

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   If your JSON has a syntax error, the error panel shows the exact line, column, and a human-readable message. Fix the highlighted character and the result re-formats automatically.

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   Click Copy to grab the formatted JSON, or click Minify to collapse it to a single line (useful for API payloads and config files).

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   Everything runs locally in your browser — no data leaves your device. You can safely paste sensitive JSON like credentials or production config.

• Debugging API responses — paste the raw response body to inspect nested structures and find the field you need.
• Inspecting JWT payloads — decode the middle segment of a JWT and paste it here to read the claims in a readable format.
• Cleaning up minified config files — expand a single-line JSON config into a readable, editable document.
• Finding syntax errors in CI/CD pipelines — paste the failing JSON to see the exact error location.
• Preparing JSON for code reviews — minified JSON is hard to review; formatted JSON makes structure obvious.

• Press Ctrl/Cmd+K to open the command palette and jump to another tool without scrolling back to the hub.
• Use the Minify button before pasting JSON into a CI/CD variable or a compact API payload — it removes all whitespace.
• If you’re debugging a JWT, decode the payload with the JWT Decoder tool, then paste the result here to format it.
• Drag a .json file from your file manager directly onto the input box to load it — no need to open it separately.
• The error reporter shows the FIRST error. Fix it and re-check — subsequent errors often disappear once the first is resolved.