JSON Formatter & Validator

• JSON requires double quotes for keys and strings.
• No trailing commas are allowed after the last item.
• This tool runs entirely in your browser – nothing is uploaded.

What this tool does

• Formatter: Adds indentation and newlines to make JSON readable.
• Minifier: Removes unnecessary whitespace to shrink JSON size.
• Validator: Checks if input is valid JSON and shows parse errors.
• Perfect for API responses, config files, and log snippets.

Tips & common issues

• JSON requires double quotes for keys and strings:{ "name": "Alice" }
• No trailing commas allowed after the last item in an object or array.
• If you see errors, check for single quotes, missing braces, or illegal comments.
• If you have comments or unquoted keys, you may be dealing with JSON5 or a JS object, which standard JSON parsers reject.