Data Types

The data types used by properties in the vocabulary.

string

A sequence of Unicode characters. No maximum length is prescribed by the vocabulary; systems should define their own limits.

FormatFree text (UTF-8)
JSON typestring

integer

A whole number with no fractional component.

FormatSigned integer (no decimal point)
JSON typenumber (integer)
Examples0, 5, -1

decimal

A numeric value that may include a fractional component. Used for scores, monetary amounts, and measurements.

FormatDecimal number
JSON typenumber
Examples99.50, -12.345, 0.0
NoteFor monetary amounts, pair with a currency property (ISO 4217 code).

boolean

A true/false value.

Formattrue or false
JSON typeboolean

date

A calendar date without a time-of-day component. Follows ISO 8601.

FormatYYYY-MM-DD (ISO 8601 calendar date)
JSON typestring
Examples2024-03-15, 1990-01-01
NoteSystems that only know a birth year may use YYYY or YYYY-01-01 with a precision qualifier. The vocabulary does not prescribe which approach to use.

datetime

A date combined with a time-of-day component. Follows ISO 8601.

FormatYYYY-MM-DDThh:mm:ssZ (ISO 8601 date-time)
JSON typestring
Examples2024-03-15T09:30:00Z, 2024-03-15T14:00:00+02:00
NoteAlways include a timezone offset or use UTC (Z). Bare local times are ambiguous.

uri

A Uniform Resource Identifier. Used for stable references to external records or resources.

FormatRFC 3986 URI
JSON typestring (format: uri)
Exampleshttps://example.org/programs/123, urn:uuid:550e8400-e29b-41d4-a716-446655440000

geojson_geometry

A geographic shape expressed as a GeoJSON Geometry object. Supports Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection.

FormatGeoJSON Geometry object (RFC 7946 §3.1)
JSON typeobject
JSON Schemahttps://geojson.org/schema/Geometry.json
Example{"type": "Point", "coordinates": [36.82, -1.29]}