JSON Formatter & Validator
Paste any JSON and this tool formats it with clean indentation, checks it for errors, or minifies it for production. It works completely in your browser — your data never leaves your device.
How to use this JSON formatter
Paste your JSON into the box above and press Format JSON. If the JSON is valid, you will see it neatly indented with two spaces, ready to read or copy. If something is wrong — a missing comma, an unquoted key, a trailing bracket — the tool tells you exactly what the parser complained about, so you can fix it fast.
Use Minify when you need the smallest possible version for an API request or a config file. The same JSON, zero wasted characters.
Working with APIs in PHP or JavaScript means working with JSON every day. If you are new to it, our guide on the difference between XML and JSON explains where JSON came from and why the whole web uses it.
Frequently Asked Questions
Is my JSON sent to a server?
No. This tool runs 100% in your browser with JavaScript. Nothing you paste is uploaded, stored or logged — you can even use it offline once the page has loaded.
What is the difference between format and minify?
Formatting adds line breaks and indentation so humans can read the JSON. Minifying removes all unnecessary whitespace so the data is as small as possible for machines. The data itself stays identical.
Why does JSON need double quotes?
The JSON standard requires double quotes around keys and string values. Single quotes, trailing commas and comments are all invalid in strict JSON — this validator will flag them for you.