JSON Formatter & Validator
Beautify, minify, and validate JSON with instant error detection and syntax highlighting.
Ready — paste JSON and click Beautify
⚙️ Indent Size
📖 JSON Cheatsheet
"key": "string"
"num": 42
"bool": true / false
"null": null
"arr": [1, 2, 3]
"obj": {…}
"num": 42
"bool": true / false
"null": null
"arr": [1, 2, 3]
"obj": {…}
What Is JSON?
JSON (JavaScript Object Notation) is a lightweight, human-readable data format used for transmitting data between servers and web applications. It supports strings, numbers, booleans, null, arrays, and objects. Its simplicity and language independence have made it the dominant data interchange format on the web.
When to Beautify vs Minify
Beautify expands JSON with indentation and line breaks — ideal for reading, debugging, and code reviews. Minify strips all whitespace to reduce file size — ideal for production APIs and bandwidth optimization. A typical JSON file can be reduced by 15–30% through minification.
What is JSON validation?
Validation checks whether your JSON conforms to the JSON spec — correct brackets, quoted keys, no trailing commas, and valid value types. Invalid JSON will break any app that tries to parse it.
Can I format JSON arrays?
Yes — top-level arrays like
[1, 2, 3] or arrays of objects are fully supported.Are there size limits?
The tool runs entirely in-browser so it can handle large JSON files limited only by your browser's memory.
Does it support JSON5 or JSONC?
No — this tool validates strict JSON (ECMA-404). Comments and trailing commas are not valid in standard JSON.