About 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.
Specifications
- Provider
- Stepfun
- Context Length
- 262,144 tokens
- Input Types
- text
- Output Types
- text
- Category
- Other
- Added
- 1/29/2026