Step 3.5 Flash
StepFun· released 29 Jan 2026
stepfun/step-3.5-flash- Input / 1M tokens
- $0.1
- Output / 1M tokens
- $0.3
Context window262K tokens
Longest answer: 66K tokens
About
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....
Details
- Lab
- StepFunopenrouter.ai · 3 Oct 2026
- Context
- 262Kopenrouter.ai · 3 Oct 2026
- Input price
- $0.1 / 1Mopenrouter.ai · 3 Oct 2026
- Output price
- $0.3 / 1Mopenrouter.ai · 3 Oct 2026
- Max output
- 65,536 tokensopenrouter.ai · 3 Oct 2026
- Inputs
- textopenrouter.ai · 3 Oct 2026
- Open weights
- Yesopenrouter.ai · 3 Oct 2026
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Sources
- openrouter.ai/stepfun/step-3.5-flash· checked 3 Oct 2026