1Overview

The Uuid scalar type represents a Universally Unique Identifier (UUID) as defined by RFC 9562. It is intended for scenarios where globally unique identifiers are required, such as database primary keys, distributed system identifiers, or any situation requiring collision-resistant unique identifiers.

Unlike the built-in ID scalar which can be any string or number, Uuid enforces the specific format and structure of UUIDs, providing stronger guarantees about uniqueness and format validity.

The scalar uses the standard UUID string representation as defined in RFC 9562.

2Recommended name

The recommended name for this scalar is Uuid.

3Result spec

A Uuid scalar must serialize to a string conforming to the UUID string representation defined in RFC 9562. This represents a UUID in the format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx where each x is a hexadecimal digit (0-9, a-f, A-F).

The format is:

• 8 hexadecimal digits
• Hyphen
• 4 hexadecimal digits
• Hyphen
• 4 hexadecimal digits
• Hyphen
• 4 hexadecimal digits
• Hyphen
• 12 hexadecimal digits

Both lowercase and uppercase hexadecimal digits are valid.

4Input spec

A Uuid scalar accepts string values conforming to the UUID string representation defined in RFC 9562, both as GraphQL literals and as JSON input values.

The input format matches the result format and must:

• Follow the pattern xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
• Contain only hexadecimal digits (0-9, a-f, A-F) and hyphens in the correct positions
• Have exactly 36 characters (32 hexadecimal digits and 4 hyphens)

Implementations should validate:

• String length is exactly 36 characters
• Hyphens are in the correct positions (after the 8th, 13th, 18th, and 23rd characters)
• All other characters are valid hexadecimal digits

query {
  user(id: "123e4567-e89b-12d3-a456-426614174000") {
    name
  }
}

{
  "id": "123e4567-e89b-12d3-a456-426614174000"
}

{
  "userId": "550e8400-e29b-41d4-a716-446655440000"
}

5References

• RFC 9562 — Universally Unique IDentifiers (UUIDs)