juniorGraphQL

What are the default Scalar types in GraphQL?

Updated Apr 28, 2026

Short answer

Scalars are the primitive leaf values of a GraphQL query. The defaults are Int, Float, String, Boolean, and ID.

Deep explanation

A GraphQL query must resolve to scalar types at the lowest level. Int is a 32-bit integer. Float is a double-precision float. String is UTF-8. Boolean is true/false. ID represents a unique identifier, serialized as a String but indicating it shouldn't be parsed as human-readable.

Real-world example

Defining the raw data points of a database record in the API schema.

Common mistakes

  • Trying to select fields inside a Scalar type (e.g., asking for `name { first }` when `name` is a String).

Follow-up questions

  • Can you create custom scalars?

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