The Shanghai company is selling the API now and says the weights follow in three weeks — a sequence that puts the pricing claim in front of anyone's ability to run the model themselves.
Model
Step 5 Preview
Step 5 Preview is an artificial intelligence model developed by StepFun. This page lists what is publicly known about the model and every benchmark result Aivio News has recorded for it, each with its own source and date.
- Developer
- StepFun
- Model
- Step 5
- Released
- September 20, 2026
- Context window
- 1,000,000
- Modalities
- Model, Image
- Status
- Announced
- Source
- stepfun.com
Benchmarks
All storiesNo verified results recorded yet.