JSON Formatter & Validator
Format, beautify, minify, and validate JSON instantly. 100% client-side — your data stays private.
JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It has become the standard format for data exchange on the web, used in REST APIs, configuration files, and data storage.
JSON supports six data types: strings, numbers, booleans, null, arrays, and objects. A valid JSON document must have either an object {} or array [] as its root element. Keys must be strings enclosed in double quotes, and values can be any valid JSON type.
This formatter and validator tool helps you beautify minified JSON for readability, minify formatted JSON for production use, and validate JSON structure to catch syntax errors. Common JSON errors include trailing commas, single quotes instead of double quotes, and unquoted keys.
The tool runs entirely in your browser using the native JSON.parse() and JSON.stringify() functions, ensuring your data is never sent to any server.
Frequently Asked Questions
JSON (JavaScript Object Notation) is a lightweight text-based data format used for data exchange. It uses key-value pairs and ordered lists to represent structured data.
Common causes include trailing commas, single quotes instead of double quotes, unquoted keys, missing brackets or braces, and invalid escape sequences.
JSON.parse() converts a JSON string into a JavaScript object. JSON.stringify() converts a JavaScript object into a JSON string, with optional formatting.