JSON Formatter
Format, validate and beautify JSON instantly with syntax highlighting.
How it works
Malformed JSON is one of the most common causes of broken API integrations, and the error messages browsers and languages give you are often unhelpful -- a vague "unexpected token" with no context. This formatter parses your raw JSON, and if it's valid, re-serializes it with clean, consistent indentation so nested objects and arrays are actually readable.
If the JSON is invalid, you get the exact parser error rather than a guess, so you can find the missing comma or unclosed bracket quickly. Choose 2-space, 4-space, or fully minified output depending on whether you're reading the JSON yourself or shipping it over the wire.
Everything runs in your browser using the native JSON.parse/stringify, so nothing you paste in is ever sent to a server -- safe to use even with real API responses or config files you'd rather not upload anywhere.
Frequently asked questions
Does this tool store or send my JSON anywhere?
No. Formatting happens entirely in your browser; your data never leaves your device.
What happens if my JSON is invalid?
You'll see the exact parser error, including the position of the problem, so you can fix it fast.
Can I minify JSON instead of formatting it?
Yes -- set indent to 0 ("Minified" option) to collapse the JSON to a single compact line, useful for reducing payload size before sending over a network.
What's the difference between formatting and validating?
Formatting re-serializes valid JSON with consistent indentation. Validating just checks whether the syntax is correct without changing anything -- use the dedicated JSON Validator if you only need a yes/no check.