JSON Formatter & Beautifier - Free Online Tool

Last Updated: April 1, 2026

Last updated: 2026-03-15

You get a 500-line JSON response from an API. It is one continuous line with no whitespace. Good luck finding the field you need. A JSON formatter turns that wall of text into readable, indented, syntax-highlighted JSON in one click.

What Our Formatter Does

Feature	What It Does	Why You Need It
Pretty print	Adds indentation and line breaks	Makes JSON readable
Syntax highlighting	Colors keys, strings, numbers, booleans	Faster visual scanning
Validation	Checks for syntax errors	Find missing commas, brackets, quotes
Tree view	Collapsible nested structure	Navigate large JSON documents
Minify	Removes all whitespace	Reduce payload size for APIs
Sort keys	Alphabetical key ordering	Consistent structure for comparison

Common JSON Errors

Trailing comma.{"a":1, "b":2,} - invalid in JSON (valid in JS).
Single quotes. JSON requires double quotes only.
Unquoted keys. All keys must be quoted strings.
Comments. JSON does not support comments.

JSON Size and Performance

Minified JSON is 20-30% smaller than pretty-printed. For API responses, always send minified. For config files and debugging, use pretty-printed.

Format your JSON - instant, free, with validation.

Open JSON Formatter →

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According to json.org, JSON is a lightweight data interchange format.

As RFC 8259 specifies, JSON text must be encoded in UTF-8.

Frequently Asked Questions

Is this coding tool free?

Yes, all developer tools on Cod-AI.com are free to use without registration.

What programming languages are supported?

We support JSON, XML, HTML, CSS, JavaScript, SQL, Base64, and many more formats.

Is my code secure?

All code is processed locally in your browser when possible, ensuring maximum privacy.

Can I use this for production code?

Yes, our tools are used by thousands of developers for real-world projects every day.

Do you offer an API?

API access is available for high-volume users. Contact us for details.

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💡 Pro Tip: Drag and drop files directly onto the tool for instant processing. Works with multiple files too!

Supported Formats

JS Python Java C++ Go Rust TS PHP

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Why Choose This Tool

🔒 100% Private

Files processed in your browser. Nothing uploaded.

⚡ Lightning Fast

AI-powered processing in seconds, not minutes.

💰 Always Free

No hidden fees, no signup, no limits.

🌐 Works Everywhere

Any device, any browser. No installation needed.

How It Works

Upload

Drop your file or paste content into the input area

Process

Click the button and let AI do the heavy lifting

Download

Get your result instantly, ready to use

User Reviews

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"This tool saved me hours of work. Simple, fast, and exactly what I needed."

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"Replaced a paid subscription with this free tool. Couldn't be happier."

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"Finally a tool that just works without asking for my email first."

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