JSON Formatter & Validator – Beautify, Minify & Check JSON
Format JSON online for free with ToolGuru. Paste messy JSON, pretty print or minify it, and validate the syntax — all in your browser, with no account.
Indentation
🔒 Your data is processed in your browser and is not uploaded to our server.
Free JSON Formatter & Validator
Use this JSON formatter online to turn minified or messy JSON into a readable tree. Pretty print with 2 or 4 spaces, validate the syntax, or minify JSON for a smaller payload. The tool runs in your browser, so you can format JSON without creating an account.
Pretty print and beautify JSON
Paste an object or array and choose Format JSON. Nested keys line up so you can scan configuration files, API responses, and logs. Formatting only changes whitespace — values stay exactly as they were.
Validate JSON online
The JSON validator checks that the input is legal JSON. If something is wrong, you get a short message and, when possible, a line number — not a JavaScript stack trace. Fix the syntax near that line and validate again.
Minify JSON
Minify strips extra spaces and line breaks. A formatted object such as {"name": "John", "age": 30} becomes compact JSON you can drop into an API body or a single-line config.
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How to Format JSON
Step 1
Paste your JSON
Drop the JSON into the input. Objects, arrays, nested values, strings, numbers, booleans, and null are all supported.
Step 2
Choose an action
Format JSON to pretty print it with 2 or 4 spaces, minify to remove extra whitespace, or validate the syntax.
Step 3
Copy or download
Copy the result, download a .json file, or clear the editor and start again. Nothing is uploaded.
Frequently Asked Questions
What is a JSON formatter?
A JSON formatter (also called a JSON beautifier or pretty printer) adds consistent indentation so nested objects and arrays are easier to read. ToolGuru formats JSON in your browser without changing the data.
How do I validate JSON online?
Paste the JSON and choose Validate. If the syntax is valid you will see a confirmation. If it is not, you will get a clear error with a line number when the browser can report one.
Does formatting change my JSON data?
No. Formatting only changes whitespace and indentation. Keys, values, types, and order stay the same.
Can I minify JSON?
Yes. Minify removes unnecessary whitespace so the JSON is compact — useful for APIs, config files, and smaller payloads.
Is this JSON formatter free?
Yes. You can format, validate, minify, copy, and download JSON at no charge. No account is required.
Is my JSON uploaded to a server?
No. Your data is processed in your browser and is not uploaded to our server.
What kinds of JSON can I format?
Objects, arrays, strings, numbers, booleans, null, and nested JSON. Invalid syntax is rejected with a readable error instead of a stack trace.
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