JSON Formatter & Validator
Instantly beautify, minify, and validate JSON payloads. 100% client-side — your data never leaves the browser.
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JSON Formatter & Validator
JSON (JavaScript Object Notation) is the lingua franca of modern APIs. A single misplaced comma or unescaped quote breaks everything. This tool uses the native browser JSON.parse() engine to instantly detect errors and then re-serializes using JSON.stringify() with configurable indentation.
Common JSON Errors
- Trailing commas —
{"a": 1, }is invalid JSON (it is valid JS) - Single quotes — all strings must use
"double quotes - Unquoted keys —
{name: "John"}is a JS object literal, not JSON
FAQ
Is my data sent to a server? No. Everything runs in the browser's JavaScript engine — no network request is made.
What is JSON minification? Minification strips all whitespace, reducing payload size. Useful for API responses and configuration files shipped to production.