Here is a basic example of a JSON Schema:

{
    "title": "Person",
    "type": "object",
    "properties": {
        "firstName": {
            "type": "string"
        },
        "lastName": {
            "type": "string"
        },
        "age": {
            "description": "Age in years",
            "type": "integer",
            "minimum": 0
        }
    },
    "required": ["firstName", "lastName"]
}

Example schemas

These sample schemas describe simple data structures which can be expressed as JSON. The “canonical url” links omit the “.json” extension, which is the correct way to reference the schema in a $ref, but is not friendly to web browsers. The larger links use “.json” for browser compatibility.

Geographic Coordinate
(canonical url)
a location as longitude and latitude
Card
(canonical url)
a microformat-style representation of a person, company, organization, or place
Calendar
(canonical url)
a microformat-style representation of an event
Address
(canonical url)
a microformat-style representation of a street address

Walkthroughs

The two examples below are step-by-step guides into building a schema:

The Space Telescope Science Institute has also published a guide aimed at schema authors.