All Models

StepFun 3.5 Flash

step Reasoning Tool Calling Open Weights

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....

Providers 2
Released Jan 29, 2026
Input Modalities text
Output Modalities text
Tarsk Use coding

Benchmarks

26
Intelligence Index

Available Providers (2)

Provider Model ID Input Cost Output Cost Context Max Output Docs
Vercel AI Gateway stepfun/step-3.5-flash $0.09/MTok $0.30/MTok 262.1K 262.1K
routing.run route/stepfun-3.5-flash $0.10/MTok $0.29/MTok 262.1K 65.5K

Capabilities

Reasoning
Tool Calling
Attachments
Open Weights
Structured Output