# Step 3.5 Flash — price & specs

Source: https://modelbank.ai/models/step-3.5-flash · updated 2026-11-12 · ModelBank

| Field | Value |
|---|---|
| Vendor | StepFun |
| Input price | $0.1 / 1M tokens |
| Output price | $0.3 / 1M tokens |
| Cached input | n/a / 1M tokens |
| Context window | 262,144 tokens |
| Max output | 65,536 tokens |
| Input modalities | text |
| Reasoning / tool use | yes / yes |
| Intelligence / coding index | — / — |
| Released | 2026-01-29 |
| Retirement date | none announced |

## 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....

## Price history

- 2026-09-24: $0.1 in / $0.3 out


JSON: https://modelbank.ai/api/v1/models/step-3.5-flash