◆ DevToolbox

JSON Formatter & Validator

Beautify, minify and validate JSON — instantly, in your browser.

Ad slot (AdSense)
About this tool
Paste any JSON and click Format to pretty-print it with 2-space indentation, or Minify to strip whitespace for the smallest size. If your JSON is invalid, the exact syntax error and position are shown so you can fix it fast. Everything runs locally in your browser — nothing is uploaded.
FAQ
Is my JSON uploaded anywhere?
No. This tool runs entirely in your browser using JavaScript. Your data never leaves your device.
Why does it say invalid JSON?
Common causes are trailing commas, single quotes instead of double quotes, or unquoted keys. The error message shows where parsing failed.
What indentation does it use?
Format uses 2 spaces. Minify removes all optional whitespace for the most compact output.