Free browser utility

JSON Formatter & Validator

Format and validate JSON locally in your browser with readable indentation and errors.


			

		

		

			

				Built for everyday workflows
				
Why use our JSON Formatter & Validator

				
Free, private and fast — everything runs in your browser, so your files and text stay on your own device.

			

			

				
Validates JSON and reports parsing errors clearly
Pretty-print with readable indentation
Minify JSON into a compact single line
100% client-side processing
No sign-up or watermark
Useful for debugging API responses and config files
			

		

		
How to use JSON Formatter & Validator

		

							
1Paste your JSON: Add the JSON text you want to format or check.

							
2Validate it: The tool checks whether the JSON is well-formed.

							
3Choose pretty-print or minify: Format it with readable indentation, or compress it to one line.

							
4Copy the result: Use the copy button to grab the formatted or minified JSON.

					

					

				
JSON Formatter & Validator — complete guide
				
JSON is strict about syntax — a missing comma, an extra trailing comma, or mismatched brackets will break parsing entirely, and the error messages from some tools aren't always easy to interpret. A dedicated validator catches these issues directly and tells you something is wrong before you paste broken JSON into code or a config file.
Pretty-printing (adding consistent indentation and line breaks) makes nested JSON far easier to read when debugging an API response or inspecting a configuration file. Minifying does the opposite — stripping all unnecessary whitespace — which is useful when you need the smallest possible payload for an API request or production config.
If you're working with raw text output alongside JSON, Markdown Previewer and URL Encoder & Decoder are handy companions for related data-cleanup tasks.
			

				

			
Frequently asked questions

			

									
Does it send my JSON to a server?
No. Parsing and formatting happen entirely in your browser.

									
What happens with invalid JSON?
The tool reports the parsing error instead of producing a misleading formatted result.

									
Can I minify JSON instead of formatting it?
Yes. Choose the minify option to compress it into a single compact line.

									
Is there a size limit on the JSON I can format?
No fixed limit — very large JSON may simply take a bit longer to process.

									
Is this tool free?
Yes, with no sign-up required.

									
Can I use this to debug an API response?
Yes, pasting a raw API response and pretty-printing it is one of the most common uses.

							

		

			

		
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