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stepfun-ai/Step-5-Preview

AI model by stepfun-ai

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Step 5 Preview StepFun's flagship model for agentic work 600B total parameters  ·  27B active parameters  ·  Up to 1M context Introduction  ·  Capabilities  ·  Specifications  ·  Performance  ·  Deployment  ·  Resources  ·  License Step 5 Preview is StepFun's flagship model for agentic work. It delivers frontier-level performance across software engineering and professional knowledge work, with particular strength in finance. Step 5 Preview is a sparse Mixture-of-Experts (MoE) model with 600B total parameters and 27B active parameters. It supports up to 1 million tokens of context and accepts text, images, and video, enabling sustained reasoning and tool use across complex tasks. Step 5 Preview supports repository-level software engineering, frontend and visual development, and programming for devices. It can navigate large codebases, coordinate changes across files, run and verify code, and iterate on the results. Step 5 Preview can carry out tasks that require repeated tool calls, execution, verification, and revision,…

stepfun-ai/Step-5-Preview on Hugging Face A short preview, not the full document.

Read the full model card ↗ · Preview checked 2026-10-29T06:51:48.977Z

Inside the original model card — Document outline
  1. Introduction
  2. Key Capabilities
  3. Software Engineering
  4. Long-Horizon Agentic Execution
  5. Professional Knowledge Work
  6. A Focus on Finance
  7. Model Specifications
  8. Performance
  9. Evaluation Notes
  10. Deployment
  11. Deployment Configurations
  12. vLLM

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Model overview

stepfun-ai/Step-5-Preview is a task-unspecified model repository published by stepfun-ai on Hugging Face. A library was not reported.

This page summarizes Hub metadata. For intended use, training data, evaluation results and limitations, consult the original model card.

Model facts

Task
Not reported
Library
Not reported
Recent downloads (30 days)
2,065
Cumulative likes
122
Hugging Face trending score
99
Reported safetensors parameters
604,339,504,832
Architecture
Step5ForConditionalGeneration
License
other
Access
Not gated by Hugging Face
Created
2026-09-20T03:15:06.000Z
Last modified
2026-10-15T01:28:10.000Z

Compatibility and lineage

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Parameter count is not a RAM/VRAM requirement. Check precision, quantization, context length and runtime compatibility in the model card; no hardware or API-cost claim is inferred here.

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Source: Hugging Face Hub. Metadata observed 2026-10-22T06:44:02.555Z. Daily imports are snapshots, not real-time monitoring.

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