Inspecting Minified REST & GraphQL API Responses
Paste single-line JSON payloads from browser network tabs, cURL outputs, or CloudWatch logs to inspect nested objects and arrays clearly.
JSON Formatter
Turn unreadable, single-line API responses and minified configuration logs into cleanly indented, human-readable JSON — or minify formatted JSON down to a compact single line for production payloads. Because parsing runs 100% locally in your browser's V8 JavaScript engine, you can safely format payloads containing private user data or API tokens.
How to Use the JSON Formatter
- 1
Paste your raw or minified JSON string into the left input editor.
- 2
Select your preferred indentation width (2 spaces, 4 spaces, or 8 spaces).
- 3
Click Format to pretty-print with clean line breaks and indentation, or click Minify to strip all unnecessary whitespace.
- 4
Review the output (or fix any flagged syntax error) and click Copy to copy the result.
Practical Use Cases
Minifying JSON Payloads for Database & Webhook Tests
Strip all line breaks and indentation from multi-line JSON fixtures so they can be passed as single-line CLI arguments or environment variables.
Formatting Production Logs Without Leaking PII
Format JSON containing customer emails, JWTs, or internal IDs safely inside your browser without sending company data to server-side pastebins.
JSON Formatter Features
Bi-Directional Beautify & Minify
Switch effortlessly between pretty-printed multi-line indentation and compact single-line minification.
Configurable 2, 4 & 8 Space Indents
Match your team's Prettier or EditorConfig indentation standard.
Exact Parser Error Reporting
Surfaces the exact JavaScript `JSON.parse()` syntax error message when input is malformed.
Runs 100% in your browser
Nothing is uploaded to a remote server, so your data and files stay strictly on your device.
Free and unlimited
No account registration, no watermarks, and no daily usage caps.
Mobile and desktop ready
Responsive layouts and comfortable touch controls that fit phones, tablets, and desktops.
Technical Specifications & Best Practices
- ✓Valid JSON requires double quotes (`"key"`) around all property names and strings, and forbids trailing commas after the last item in an object or array.
- ✓Formatting or minifying modifies only whitespace outside of string literals — your keys, values, and array ordering remain 100% identical.
- ✓Handles multi-megabyte JSON documents smoothly in local browser memory.
- ✓Zero network calls — verify in your browser's DevTools Network tab that your JSON never leaves your machine.