How do I format JSON?

Paste JSON above and pick an indent size. Valid input becomes indented text you can copy.

How do I make JSON readable?

Pretty-print it with consistent indentation and line breaks. This formatter does that automatically.

Can I format large JSON files?

Yes for typical API payloads in the browser. Extremely large files may be slower depending on device memory.

How do I validate JSON while formatting it?

This tool parses first. Invalid JSON shows an error instead of partial output.

What is pretty-printed JSON?

Pretty-printed JSON adds indentation and newlines so humans can scan structure without changing the data.

What is JSON Formatter?

A free online tool that pretty-prints JSON for developers and students.

How does the JSON Formatter work?

It parses your text with JSON.parse, then JSON.stringify with a chosen spacing value.

How do I use the JSON Formatter?

Paste input, select indent, and copy the formatted output panel.

Is this JSON Formatter free to use?

Yes. It is free with no sign-up.

Can I use the JSON Formatter on mobile?

Yes. It works on mobile browsers.

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Developer

JSON Formatter

Turn minified JSON into readable, indented output. Validates while formatting so broken payloads fail fast.

Runs in your browser — your data stays on your device

Free tool

Minified API responses are hard to read in a hurry. This free JSON formatter pretty-prints valid JSON with 2- or 4-space indentation so frontend developers and students can inspect nested objects during coding practice—without installing an editor plugin.

How to use the JSON Formatter

1
Paste minified or messy JSON.
2
Choose 2-space or 4-space indent.
3
Copy the pretty-printed result once validation succeeds.

Why pretty-printing speeds up reviews

Collapsed payloads hide missing fields and wrong nesting. Formatting while validating gives you both confidence and readability—exactly what API response debugging needs in JavaScript coursework and day-to-day web development.

Pretty-print example

Paste a one-line object with nested meta data, choose 2-space indent, and watch keys align vertically. That pretty-printed JSON is what most teams paste into tickets and pull requests.

Guides and next steps

Privacy note

Formatting runs entirely in your browser. Your JSON never leaves your device.

Frequently asked questions

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