Open-weight MoE model
StepFun's Step 5 Preview is an open-weight mixture-of-experts model with 600 billion total parameters and 27 billion active parameters per token.
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Step 5 Preview
Open-weight 600B MoE model with 27B active parameters and a 1M-token context for coding and agent tasks.
Product brief
What Step 5 Preview does.
Step 5 Preview is StepFun's open-weight MoE for coding, financial research and long-running agents. It has 600B total parameters, 27B active per token and a 1M-token context, with deployment support for vLLM, SGLang and Transformers.