What is the difference between Sequential and Functional API in Keras?

Updated May 16, 2026

Short answer

Sequential is linear; Functional API supports complex architectures.

Deep explanation

Functional API allows multiple inputs/outputs, shared layers, and DAG-style networks.

Real-world example

Used in multi-modal models combining image and text inputs.

Common mistakes

  • Using Sequential for complex architectures.

Follow-up questions

  • When to use Functional API?
  • Can both APIs be mixed?

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