# Step 3.5 Flash 2603

`step-3.5-flash-2603` — **stepfun** · CHAT

> Step 3.5 Flash 2603 (step-3.5-flash-2603) is a chat model from stepfun with a 256K-token context window; open-weight; capabilities tools, reasoning; input text; output text.

| Field | Value |
| --- | --- |
| Vendor | stepfun |
| Kind | CHAT |
| Context window | 256,000 tokens |
| Max output tokens | 256,000 tokens |
| Indicative price (US list) | $0.10461 in / $0.31384 out per 1M tokens (indicative US list — verify with vendor) |
| Input modalities | text |
| Output modalities | text |
| Capabilities | tools, reasoning |
| Weights | Open-weight |
| Knowledge cutoff | 2025-01 |
| Release date | 2026-04-02 |
| Sources | models-dev |
| Last verified | 2026-10-30 |

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