How to Format JSON Online

Format, validate, and beautify JSON instantly in your browser. Free JSON formatter with syntax highlighting, error detection, and minification.

Open JSON Formatter →

Step-by-Step Guide

1

Paste your JSON

Copy your raw JSON data and paste it into the input area. The tool accepts any valid JSON — objects, arrays, nested structures, or API responses.

2

Click Format

Hit the "Format" button. The formatter validates your JSON, adds proper indentation (2 or 4 spaces), and applies syntax highlighting so you can read it easily.

3

Fix errors if needed

If your JSON has syntax errors (missing commas, unquoted keys, trailing commas), the tool highlights the exact line and character position so you can fix it quickly.

4

Copy or minify

Copy the formatted result to your clipboard, or switch to "Minify" mode to compress it for production use. Everything runs locally — your data never leaves your browser.

Try It Now — Free

No signup, no download. Runs entirely in your browser.

Open JSON Formatter

Frequently Asked Questions

Is my JSON data safe?
Yes. The formatter runs entirely in your browser using JavaScript. Your data is never sent to any server.
What JSON errors can it detect?
Missing commas, unclosed brackets, unquoted keys, trailing commas, duplicate keys, and invalid escape sequences.
Can I format large JSON files?
Yes. The tool handles files up to several megabytes without issues since all processing happens locally.
Related Reference

JavaScript Cheat Sheet

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