Format a JSON API response
Paste raw JSON returned by an API to make it readable, inspect nested objects and arrays, and copy the formatted output.
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JSON Formatter and Validator Online
If you are working with API payloads or encoded data, you may also want to try our JSON tools or our encoding tools.
Related tools
- Estimate LLM tokens to estimate the size and cost of JSON used in prompts, payloads or AI workflows.
- Encode and decode Base64 to encode or decode payloads and strings used in API integrations.
- Decode JWT to inspect header and payload when your JSON comes from a token.
How it works
Format, validate and minify JSON directly in your browser. Paste raw JSON, make it readable, catch parsing errors and copy the result without sending data to external servers.
Practical examples
Validate JSON before using it in code
Catch common JSON errors such as missing commas, invalid brackets, unclosed strings or malformed objects before using the data in your app.
Minify JSON for HTTP payloads and config files
Switch to Minified view when you need compact JSON for API requests, environment variables, configuration files or test fixtures.
FAQ
Is the JSON sent to a server?
No. Formatting, validation and minification happen locally in your browser.
Can this tool validate invalid JSON?
Yes. If the JSON is malformed, the tool shows a parsing error so you can quickly fix the problem.
Can I minify JSON?
Yes. Use the Minified view to create compact JSON for API payloads, configuration files or environment variables.
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