JSON Formatter & Validator
Format, validate, and beautify JSON online. Free, instant, and works entirely in your browser — your data is never uploaded.
About the JSON Formatter
JSON (JavaScript Object Notation) is the lightweight data format powering most modern web APIs. Minified JSON is compact but hard to read; formatted JSON is readable but verbose. This tool converts between the two in a single click, and validates the structure at the same time.
How to use
Paste your JSON into the left editor and press Format. If the JSON is invalid, an error message appears with the line and column of the first problem. Use Minify to strip whitespace, or Validate to just check correctness without changing the output. Pick 2 spaces, 4 spaces, or a tab from the indent selector to match your code style. Press Ctrl/⌘ + Enter as a shortcut to format.
Privacy
Your JSON never leaves this browser. All parsing and formatting runs locally — nothing is uploaded, logged, or stored. Close the tab and the data is gone.