What is JSON?

JSON (JavaScript Object Notation) is a lightweight, text-based format for storing and exchanging data. It represents data as key-value pairs and ordered lists, is easy for both people and machines to read, and is the most widely used data format for APIs and web applications today.

{
  "name": "Ada Lovelace",
  "age": 36,
  "active": true,
  "roles": ["admin", "editor"],
  "address": { "city": "London" }
}

What JSON is made of

• Objects: unordered collections of key-value pairs wrapped in curly braces { }
• Arrays: ordered lists of values wrapped in square brackets [ ]
• Values: a string, number, true, false, null, object, or array
• Keys: always strings wrapped in double quotes

Where JSON is used

• REST and GraphQL APIs, the default way web services send and receive data
• Configuration files such as package.json and tsconfig.json
• NoSQL databases like MongoDB, and log/analytics events
• Data exchange between almost any two systems or languages

Work with JSON instantly

Paste any JSON into the JSON Copilot editor to format it, validate it, or explore it as a tree or mind map, all in your browser. New here? See Getting Started.