StepFun
Step 3.5 Flash
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....
Cost / 1M tokens
Very low usage$0.10
input
—
cached input
$0.30
output
Context Window
262K
Up to 66K max output
Modalities
text → text
Other tokenizer
Quickstart & API
stepfun/step-3.5-flashBest for & Strengths
Key Strengths
Recommended Workloads in ChatOSS
- Coding agents
- Complex reasoning & debugging
- Open-source AI workflows
Active Provider Endpoints (1)
Upstream inference providers serving Step 3.5 Flash, with per-provider pricing, context limits, quantization, and 24-hour uptime.
| Provider | Input / 1M | Output / 1M | Cache Read / 1M | Context | Max Output | Quantization | Uptime (24h) |
|---|---|---|---|---|---|---|---|
SiliconFlow siliconflow/fp8 | $0.10 | $0.30 | — | 262K | 66K | fp8 | 99.9% |
Supported API Parameters
Parameters accepted by this model when called through ChatOSS or OpenRouter.
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