Input
$0.10
Output
$0.30
Context
256K
Step 3.5 Flash costs $0.10 per million input tokens and $0.30 per million output tokens.
Specifications
| Lab | StepFun |
| Model id | stepfun/step-3.5-flash |
| Input price | $0.10 per million tokens |
| Output price | $0.30 per million tokens |
| Cached input price | $0 per million tokens |
| Context window | 262,144 tokens (256K) |
| Maximum output | 65,536 tokens (64K) |
| Tool calling | yes |
| Image input | no |
| Reasoning | yes |
| First listed | 29 January 2026 |
StepFun's other models
| Model | Input / 1M | Output / 1M | Context | Listed |
|---|---|---|---|---|
| Step 5 Preview | $1 | $2.70 | 1M | 8 October 2026 |
| Step 3.7 Flash | $0.20 | $1.15 | 256K | 28 May 2026 |
Where these numbers come from
Read from OpenRouter's listing of Step 3.5 Flash every 6 hours into the catalog Founden's builders choose their models from. Prices are OpenRouter's listed price per million tokens: for a lab's closed models that is the lab's own list price, and for an open-weight model it is the price of the host OpenRouter routes to by default, which can differ from the lab's own API and from other hosts. US dollars, before batch, volume or regional discounts. Every model.