JSON Formatter

What is JSON Formatter?

A JSON formatter re-indents minified or messy JSON into a readable, properly nested structure while validating the syntax and pointing to the exact line and column of any error. Parsing runs on your own machine through the browser's built-in JSON engine, so the text you paste is never uploaded to a server.

How to use JSON Formatter

1. 1Paste your JSON into the input box on the left; the tool parses it as you type.
2. 2Use the indentation selector to output 2 spaces, 4 spaces, or tabs.
3. 3Click "Minify" for a single-line JSON string with every bit of whitespace removed — ideal for config values and URL parameters.
4. 4If the syntax is invalid, the right-hand pane shows the error position along with the raw parser message so you can fix it and re-parse.

How do I do this in code?

Use the tool above for one-off work; for anything you repeat, move it into a script or your project.

// Pretty-print: the third argument is the number of spaces to indent
const pretty = JSON.stringify(JSON.parse(raw), null, 2);

// Minify: simply omit the third argument
const minified = JSON.stringify(JSON.parse(raw));

Common errors and how to fix them

Frequently asked questions