JSON Formatter & Validator

Paste JSON to format, validate, and minify instantly. Real-time error detection, 2 or 4-space indent, one-click copy.

Indent
Formatted JSON will appear here…

About This Tool

Format and validate JSON without leaving your browser

Paste any JSON — from an API response, a config file, or a log — and get instant formatting with syntax validation. Errors are caught in real time with the exact message from the parser so you can fix them immediately.

Need to encode the result for a URL? Use the URL Encoder. Working with text? Try the Word Counter.

Real-Time Validation

Errors are shown instantly as you type, with the exact parser message.

Format & Minify

Prettify for readability or minify to a single line for APIs.

2 or 4-Space Indent

Choose your preferred indentation style from the toolbar.

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100% Private

No upload — your JSON is processed locally in your browser.

Quick Start

How to Format JSON

01

Paste Your JSON

Paste raw, minified, or malformed JSON into the input panel. Validation runs automatically as you type.

02

Choose Indent Size

Select 2-space or 4-space indentation. The output updates instantly.

03

Copy or Minify

Click Copy to grab the formatted output, or Minify to collapse it to a single line for use in code.

FAQ

Frequently Asked Questions

Does this upload my JSON anywhere?

No. All formatting and validation happens locally in your browser. Your data never leaves your device.

What counts as valid JSON?

Double-quoted keys and strings, no trailing commas, no comments, correct nesting of {} and []. The validator shows the exact error if something is wrong.

What is the difference between Format and Minify?

Format adds indentation for readability. Minify removes all whitespace — useful for APIs and config files.

Why is my JSON showing an error?

Common causes: trailing commas, single-quoted strings, unquoted keys, or missing brackets. The error message will tell you exactly what went wrong.

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