JSON Formatter
Format, validate and minify JSON with precise error positions.
JSON
Formatted JSON appears here.
Private by design. Everything runs locally in your browser. Your input is never uploaded, logged or stored on a server.
Frequently asked questions
What is a JSON formatter?
It re-indents JSON so nested objects and arrays line up, making the structure readable. This tool also parses the input, so invalid JSON is rejected with the exact position of the problem instead of a generic error.
Is this JSON formatter free?
Yes. There is no signup, no usage limit and no paid tier for this tool.
Does this tool upload my JSON?
No. Formatting happens with the browser built-in JSON parser on your own machine. Nothing is sent over the network, so it is safe for payloads that contain internal data.
Why does my JSON fail to parse?
The four most common causes are a trailing comma after the last item, single quotes instead of double quotes, unquoted object keys, and a raw newline inside a string. The error message points at the first character the parser could not accept.
How large a document can it handle?
Documents up to a few megabytes format instantly. Very large files are limited by your browser memory rather than by the tool.
About the JSON Formatter
A JSON formatter turns a single unreadable line of JSON into an indented, scannable document. This one also validates: when the parser fails it reports the line and column where it gave up, which is usually a trailing comma, a single quote where a double quote belongs, or an unescaped control character.
Sort keys alphabetically when you need to diff two API responses that return object keys in a different order, and minify before pasting a payload into an environment variable or a URL.