StepFun Releases Step 5 Preview Open Weights: 600B MoE, 27B Active, 1M Context
StepFun has released Step 5 Preview as open weights.
Proof1 independent outlet1 community thread
Key points
- FP8 and BF16 checkpoints are live on Hugging Face and ModelScope.
- Step 5 Preview is a sparse Mixture-of-Experts model from StepFun built for long-horizon agentic work.
- Size: 600B total, 27B active per token, up to 1M-token context.
- Step 5 Preview is StepFun's flagship model for agentic work.
Sources (2)
- [1]StepFun Releases Step 5 Preview Open Weights: 600B MoE, 27B Active, 1M ContextMarkTechPost · Oct 17, 06:29 AM
StepFun has released Step 5 Preview as open weights.
FP8 and BF16 checkpoints are live on Hugging Face and ModelScope.
- [2]Stepfun Step-5-Preview released! (600B/27B-1M Context)r/LocalLLaMA (top, daily) · Oct 15, 06:04 AM
Step 5 Preview is StepFun's flagship model for agentic work.
Extractive summary: sentences quoted from the sources.
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