Introducing Step 5 Preview: Advancing the Pareto Frontier.

Step 5 Preview is our new flagship model for agentic work, delivering frontier-level performance across software engineering and professional knowledge work, with particular strength in finance.

• 600B total / 27B active MoE, with 1M context + Vision
• Substantially lower task cost at comparable intelligence
• Broad software engineering capabilities with sustained execution over long horizons

Try Step 5 Preview: https://platform.stepfun.ai
Model page: https://www.stepfun.com/step-5-preview

Open weights on Oct 15.