# Step 5 Preview

`step-5-preview` — **stepfun** · CHAT

> Step 5 Preview (step-5-preview) is a chat model from stepfun with a 1M-token context window; open-weight; capabilities tools, vision, reasoning; input image, text, video; output text.

| Field | Value |
| --- | --- |
| Vendor | stepfun |
| Kind | CHAT |
| Context window | 1,000,000 tokens |
| Max output tokens | 65,536 tokens |
| Indicative price (US list) | $1.04613 in / $2.98895 out per 1M tokens (indicative US list — verify with vendor) |
| Input modalities | image, text, video |
| Output modalities | text |
| Capabilities | tools, vision, reasoning |
| Weights | Open-weight |
| Release date | 2026-09-16 |
| Sources | models-dev |
| Last verified | 2026-10-30 |

*Part of the [Model Catalog](https://openviglet.github.io/model-catalog/) — [stepfun models](https://openviglet.github.io/model-catalog/models/stepfun/) · [Vendor JSON](https://openviglet.github.io/model-catalog/by-vendor/stepfun.json) · [HTML](https://openviglet.github.io/model-catalog/models/stepfun/step-5-preview.html)*