JSON Formatter & Validator
Pretty-print, minify and validate JSON.
Output
About the JSON Formatter & Validator
Format, validate and minify JSON instantly in your browser. Paste messy JSON to pretty-print it with proper indentation, or minify it for production — with clear error messages when the syntax is invalid.
How to use it
- 1Paste or type your JSON.
- 2Choose format (pretty-print) or minify.
- 3Copy the cleaned-up result, or read the error if the JSON is invalid.
Format, minify and validate — and when to use each
Pretty-printing adds consistent indentation and line breaks so a wall of JSON becomes readable — ideal while you're debugging an API response or reviewing a config file. Minifying strips all that whitespace to produce the smallest possible payload, which is what you want in production where every byte counts. Validation runs on every keystroke: if the JSON is malformed, you get a precise error instead of a silent failure, which saves the guesswork of hunting for a stray comma or bracket.
Common uses
- Cleaning up a minified API response so it's readable while debugging.
- Minifying a JSON config or payload before shipping it to production.
- Validating hand-edited JSON to catch syntax errors before use.
Frequently asked questions
- Is my JSON sent anywhere?
- No. Parsing, validating and formatting all happen locally in your browser.
- Why does it say my JSON is invalid?
- Common causes are trailing commas, single quotes instead of double quotes, missing brackets, or unquoted keys. The error message points to where parsing failed so you can fix it quickly.