JSON Formatter

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It's easy for humans to read and write, and easy for machines to parse and generate. APIs, config files, and data storage commonly use JSON.

Absolutely. Everything runs locally in your browser - your JSON never leaves your computer. No data is uploaded to any server.

Common causes: trailing commas after the last item, single quotes instead of double quotes, unquoted keys, or comments (JSON doesn't support comments). The error message will point to the approximate position of the issue.

Yes. Copy the formatted output and paste it back into the input, removing all spaces and line breaks manually. For one-click minification, use a dedicated JSON minifier tool.

JSON requires double-quoted keys and string values, doesn't support trailing commas, comments, or undefined values. JavaScript objects are more flexible but JSON is the standard for APIs and data exchange.

The tool handles files up to ~50MB in most modern browsers. For very large files, the browser's memory limits may apply. For API responses and config files (typically under 1MB), formatting is instant.

Yes, the formatter handles large payloads efficiently. However, for files over ~50MB, your browser's memory limits may apply. For most API responses and config files, it's instant.