StepFun: Step3
By Stepfun Ai
Released: 2025-08-28
Stepfun AI Step3 features 38B parameters, MoE architecture and 66k-token context window. Step3 is a cutting-edge multimodal reasoning model, built on a Mixture-of-Experts architecture with 321B total parameters and 38B active. It is designed end-to-end to minimize decoding costs while delivering top-tier performance in vision–language reasoning. Through the co-design of Multi-Matrix Factorization Attention (MFA) and Attention-FFN Disaggregation (AFD), Step3 maintains exceptional efficiency across both flagship and low-end accelerators. Premium pricing at $0.57/1M tokens reflects its advanced capabilities.
Visit StepFun: Step3AI-Powered
Leverages advanced AI technology to deliver cutting-edge capabilities and results.
Fast & Efficient
Optimized performance ensures quick results without compromising on quality.
Purpose-Built
Specifically designed for llms tasks and workflows.
Stepfun Ai Model Timeline
66k tokens context
Specifications
AI Evaluation
Optimized for programming tasks, this model excels at code generation, debugging, and software engineering workflows with solid benchmark performance.
Pros
- Strong code generation and debugging
- Advanced logical reasoning
- Image and visual analysis
- Multi-modal input support
Cons
- Moderate API costs
- May lack creative flair
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