Step 3.5 Flash
Stepfun馃嚚馃嚦
stepfun/step-3.5-flashStep 3.5 Flash is StepFun's flagship sparse MoE reasoning model (196B parameters, 11B active) built for fast, reliable execution of complex tasks. It excels at decomposing and planning multi-step problems and orchestrating tool calls, making it well suited for agentic and coding workflows.
Cost rate
0.1x
Context
262K
Released
Jan 29, 2026
Input
Text
Output
Text
Support
ReasoningTool callingStructured outputs
Best at
The categories where this model ranks highest.
Mathematical
#132 路 top 34%
Software & IT Services
#156 路 top 38%
Business, Management, & Finance
#170 路 top 42%
Writing, Literature, & Language
#176 路 top 43%
Performance
Median latency and throughput measured across recent requests.
Throughput119 tok/s
Latency