Compatibility warning
This specification extension is supported only in OpenAPI 2.0. In OpenAPI 3.0, use nullable. In OpenAPI 3.1, use an array of types and include null in the list.
Use x-nullable in your OpenAPI 2.0 documents to mark schemas with the label Nullable in the API documentation. This indicates that the value of a particular property may be null. Add it to the schema OpenAPI object.
Use the x-nullable extension in an Schema object.
| Option | Type | Description |
|---|---|---|
| x-nullable | boolean | Marks schema as a nullable. |
The following example show how to mark the country Schema as nullable.
swagger: '2.0'
schemas:
country:
type: string
description: Country of origin
x-nullable: true- Migration notes from OpenAPI 3.0 to 3.1 - Learn about nullable changes and migration considerations between OpenAPI versions
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