JSON Formatter & Validator

What this does

Developers use JSON formatters dozens of times a day to make API responses readable, spot syntax errors, and shrink payloads. This one tells you the exact line of any error, supports tab or space indentation, and never sends your data anywhere.

Format, validate, minify — what's the difference?

• Format (pretty-print): adds indentation and line breaks so a wall of JSON becomes a readable tree.
• Validate: checks that the JSON is syntactically correct and points you to the exact problem if it isn't.
• Minify: strips every unnecessary space and newline to make the payload as small as possible for transmission.

Common JSON errors it catches

• Single quotes instead of double quotes around keys or strings.
• A trailing comma after the last item in an object or array.
• A missing closing } or ].
• Unescaped special characters inside strings.

New to the format? Our guide on what JSON is and how to format it explains the structure from scratch.

Private by default

API responses often contain tokens, personal data, or business logic you don't want leaking. Because this formatter runs entirely in your browser, the JSON you paste is never uploaded or logged — it's safe for sensitive payloads, and it works offline once the page has loaded.