StepFun
10 models across 1 family · Latest: Step 3.5 Flash (2026-01)
One of China's leading AI 'Six Tigers'.
StepFun is a Chinese AI company founded in 2023. One of China's leading AI 'Six Tigers'. StepFun ships 1 model family totaling 10 models, with the most recent release Step 3.5 Flash in 2026-01. Notable families include Step. Use it as a stable reference for lab background, release coverage, and follow-up model pages as they are added. Researchers and evaluators can scan counts, links, release history, and source references without leaving the directory.
About
StepFun (阶跃星辰) is a Chinese AI startup founded in April 2023 that develops large-scale foundation models for text generation, multimodal understanding, and audio processing. The company released the Step-1 language model with hundreds of billions of parameters, the Step-1V multimodal model, and a preview of the Step-2 trillion-parameter MoE language model. Their latest open-source release, Step-3.5-Flash, is optimized for efficient local inference and agentic intelligence.
Featured models
| Model | Released | Context | Input price ($/1M) | Output price ($/1M) | License |
|---|---|---|---|---|---|
| Step 3.5 Flash | 2026-01-29 | 256K | $0.10 | $0.30 | Proprietary |
| StepFun Step-2 | 2025-10-15 | 128k | - | - | Proprietary |
| StepFun Step-1 | 2025-08-20 | 128k | - | - | Proprietary |
Model families
Recent releases
- Step 3.5 Flash- 2026-01-29
- StepFun Step-2- 2025-10-15
- StepFun Step-1- 2025-08-20
- Step-2- 2024-09-01
- Step-1V Turbo- 2024-07-01
FAQ
Who founded StepFun and when?
StepFun was founded in 2023 and is associated with Shanghai, China.
What models has StepFun released?
StepFun ships 10 models across 1 family: Step.
Is StepFun's technology open source?
Some StepFun models are open-weight (Step 3.5 Flash); others are proprietary (StepFun Step-2, StepFun Step-1, and Step-2).
Where is StepFun headquartered?
StepFun is headquartered in Shanghai, China.
What is StepFun known for?
One of China's leading AI 'Six Tigers'. Its most prominent tracked family is Step.
How can I access StepFun's models?
StepFun's models are available via OpenRouter and StepFun.
Explore related pages
Last reviewed: 2026-04-20. Data sourced from public lab announcements and provider documentation.