Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters). It performs strongly in software engineering and professional...
Model catalog
Models
Every model in the catalog with source-linked pricing, context limits, provider availability, and published benchmark results.
17 providers
Step 3.7 Flash is StepFun's latest high-efficiency multimodal Mixture-of-Experts model. It pairs a 196B-parameter language backbone with a vision encoder for native image and video understanding, activating roughly 11B parameters...
21 providers
StepFun flash model for efficient multimodal reasoning, coding, and tool use
6 providers
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....
15 providers
| Model | Creator | Inputs | Context | Input | Output | Released | Compare |
|---|---|---|---|---|---|---|---|
| StepFun: Step 5 Previewstepfun/step-5-preview | 1M | $1 | $2.7 | 2026-09-16 | |||
| StepFun: Step 3.7 Flashstepfun/step-3.7-flash | 256K | $0.2 | $1.15 | 2026-05-29 | |||
| Step 3.5 Flash 2603stepfun/step-3.5-flash-2603 | 256K | $0.105 | $0.314 | 2026-04-02 | |||
| StepFun: Step 3.5 Flashstepfun/step-3.5-flash | 262.144K | $0.1 | $0.3 | 2026-01-29 |