Format & validate
JSON instantly. Free.

JSON (JavaScript Object Notation) is a lightweight, text-based data format used to store and exchange structured information. It is the most widely used format for APIs, web services, configuration files, and data storage. JSON is human-readable and language-independent, making it the standard for communication between servers and web applications.

The formatter takes raw or minified JSON text and reformats it with proper indentation, line breaks, and syntax highlighting to make it easy to read and understand. It also validates the JSON — if there are any syntax errors (missing quotes, trailing commas, unmatched brackets), it highlights the problem and tells you where the error is so you can fix it.

JSON validation checks whether the text you have entered is valid, well-formed JSON according to the official specification. Invalid JSON will fail silently or throw errors in applications, APIs, and databases. Validating before use saves debugging time and prevents runtime errors in your code.

Formatted JSON has indentation, line breaks, and spacing that make it easy for humans to read. Minified JSON removes all whitespace and line breaks, resulting in a compact single-line string that is smaller in size. Minified JSON is used in production environments and APIs to reduce bandwidth and file size, while formatted JSON is used during development and debugging.

Yes. Paste your JSON into the editor and the formatter will immediately highlight any syntax errors and indicate the line and position where the problem occurs. Common issues include missing commas between values, trailing commas (which are not allowed in JSON), unquoted keys, mismatched brackets or braces, and incorrect use of single quotes instead of double quotes.

JSON is a text format — it is always a string. JavaScript objects are in-memory data structures. They look similar but have key differences: JSON requires all keys to be in double quotes, does not allow trailing commas, does not support functions or undefined values, and does not allow comments. A JavaScript object is more flexible but cannot be directly transmitted or stored without serialization.

The formatter runs entirely in your browser, so the practical limit depends on your device's available memory. For typical use cases — API responses, config files, data exports — the tool handles files of any reasonable size smoothly. Extremely large files (tens of megabytes) may slow down the browser tab on older devices.

Yes. The formatter works with any valid JSON content, including configuration files like package.json, tsconfig.json, .eslintrc.json, and similar files used in development projects. Paste the content, format it, and copy it back. This is useful for cleaning up manually edited config files that may have inconsistent indentation.