stepfun

StepFun: Step 3.5 Flash

Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token. It is a reasoning model that is incredibly speed efficient even at long contexts.

Input Cost

$0.10

per 1M tokens

Output Cost

$0.30

per 1M tokens

Context Window

256,000

tokens

Compare vs GPT-4o

                Developer ID: stepfun/step-3.5-flash            

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