Paste JSON, get pretty-printed or minified output instantly, and catch syntax errors as you go.
This free online JSON formatter cleans up messy, minified, or hand-edited JSON so it's actually readable — paste any JSON object or array below and click Format to pretty-print it with proper indentation, or Minify to strip whitespace for production use. If the JSON is invalid, it tells you exactly what's wrong instead of just failing silently.
JSON (JavaScript Object Notation) is the standard format for data exchanged between APIs, config files, and countless developer tools — but it's frequently delivered minified into one dense, unreadable line, or hand-typed with a missing comma or unclosed bracket. This tool solves both problems: Format re-indents your JSON with 2-space nesting so you can actually read the structure, while Minify does the reverse — stripping all unnecessary whitespace down to the smallest valid representation, which is what you want before shipping JSON to production.
Along the way, it validates the JSON against the spec. If something's wrong — a trailing comma, a missing quote, mismatched brackets — you'll get a specific error message pointing at the problem instead of a blank screen, which makes it useful for quickly debugging malformed API responses or config files.
Everything runs as JavaScript inside your own browser tab; nothing you paste here is ever sent to a server, so it's safe to use with real API responses, internal config, or anything else you wouldn't want to paste into a random website.