Format, beautify, and validate JSON online for free. Instantly minify or prettify JSON with syntax error detection. No signup, runs in your browser.
Beautify or minify JSON instantly in your browser. Paste a raw API response, config file, or database export and the tool formats it with 2- or 4-space indentation for readability — or collapses it into a single line for storage and transmission. Syntax errors are highlighted as you type so you can fix invalid commas, unquoted keys, and mismatched braces immediately. Everything runs locally — your JSON never leaves the browser tab. Free, with no size limit, no signup, and no rate limits.
How It Works
Paste Your JSON
Copy raw JSON from an API response, config file, or database export and paste it into the input area. Formatting updates in real time as you type.
Choose Beautify or Minify
Switch to Beautify for indented, human-readable JSON — choose 2 or 4-space indent. Switch to Minify to collapse everything into a single line for production or storage.
Copy the Output
Click Copy next to the output panel to grab the formatted or minified JSON and paste it directly into your code editor, API client, or config file.
Use Cases
API Developers
Quickly inspect minified API responses during debugging without setting up a local environment — paste the raw response and read it instantly.
Frontend Engineers
Validate JSON config files and environment schemas before deploying to catch syntax errors early — misplaced commas and unquoted keys are highlighted immediately.
DevOps & Backend Teams
Minify JSON payloads before storing in databases or sending over the wire to reduce size, then beautify again when you need to read or edit them.
FAQ
Everything you need to know before you start.
Paste your JSON into the input box. The formatter validates and beautifies it instantly as you type. If there is a syntax error, the error message shows exactly what is wrong.
Beautify adds indentation and line breaks to make JSON human-readable. Minify removes all whitespace to produce the smallest possible string — useful for API responses and reducing file size.
Yes. It uses the browser's native JSON.parse(), which catches all standard syntax errors including missing commas, unquoted keys, trailing commas, and mismatched brackets.
No. The entire tool runs in your browser. Your JSON never leaves your device — it is not transmitted or stored anywhere.
Yes. Switch between 2-space and 4-space indentation using the indent buttons in Beautify mode. 2 spaces is most common for web APIs; 4 spaces is preferred in many enterprise codebases.
More Free Tools
Good to know
Malformed JSON is one of the most common sources of API bugs — a trailing comma or an unescaped quote breaks the whole payload. Beautifying JSON makes nested structures readable so you can actually see what an API returned, while validation catches syntax errors at the exact line. Because this runs entirely client-side, you can safely paste API responses, config files, and tokens without anything being sent to a server.
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