JSON Formatter & Validator Online Free (Beautify JSON)

An API response arrives as one long unreadable line. A config file will not load because of a missing comma somewhere. The PDFFlowState JSON Formatter and JSON Validator fix both in your browser, for free, with no account.

• Open JSON Formatter
• Open JSON Validator

What do they do?

• JSON Formatter formats, minifies and validates JSON. It works as a JSON beautifier, taking compact or messy JSON and making it easy to read. It also minifies JSON when you want it small. It is useful as a JSON formatter and validator in one step.
• JSON Validator finds syntax errors before JSON reaches an API. Use it as a JSON checker online to validate JSON online and verify JSON before you send it.

How to format JSON

1. Open the tool. Go to JSON Formatter. It works on phone and desktop.
2. Paste your JSON. Drop in the raw text.
3. Format. Choose to format it (or minify it) and read the result.
4. Copy. Use the cleaned-up JSON in your code, docs or API tests.

How to validate JSON

1. Open JSON Validator.
2. Paste your JSON.
3. Check. The tool tells you whether it is valid and helps you find the error if it is not.
4. Fix and re-check until it passes.

No sign-up is needed for either tool, so both are free JSON formatter online options.

Common JSON mistakes the validator catches

• A missing or extra comma
• Single quotes instead of double quotes
• Unquoted keys
• A trailing comma after the last item
• Unclosed brackets or braces
• Comments, which standard JSON does not allow

When is it useful?

• Reading API responses and debugging requests.
• Editing config files without breaking them.
• Checking data before you post it to an API.
• Minifying JSON for production or to save space.
• Teaching and documentation, where readable examples matter.

Related tools

• Convert JSON to CSV or XML with CSV Converter.
• Decode a Base64 string that contains JSON with Base64 Encode and Decode, then format the result here.
• Compare two JSON versions with Diff Checker.
• Pull values out with Regex Tester.

Frequently asked questions

Is this JSON formatter free? Yes. Both tools are free and need no sign-up.

What is the difference between formatting and validating JSON? Formatting makes JSON readable (or compact). Validating checks that it follows the JSON rules. The formatter does both, and the validator focuses on finding errors.

Can I use it as a Chrome extension? There is no extension to install. It is a web tool that works in any browser.

Is there a download or desktop version? No download is needed. Open it in your browser.

Can I validate JSON against a schema? Not at the moment. The tools check JSON syntax.

Can I convert JSON to CSV? Yes, with CSV Converter.

Format your JSON now

Try JSON Formatter, try JSON Validator or browse all the developer tools on PDFFlowState.