# Step (slim)

> Step, a family of models by StepFun, listed from OpenRouter. Indexed, not reviewed: facts and our own checks, no score or ranking. Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters).…

- Full: https://www.anchorterminal.com/tools/step.md (~500 tokens) · this version ~430 tokens · JSON https://www.anchorterminal.com/tools/step.json · canonical https://www.anchorterminal.com/tools/step
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-08

# Step

> Indexed, not reviewed: facts from OpenRouter and our own checks. No score, grade or rank, and not in the rankings until the panel reviews it. How the index works: https://www.anchorterminal.com/indexed/

- Kind: model family, by StepFun
- Category: Model APIs & inference (https://www.anchorterminal.com/categories/inference.md)
- Listed because: OpenRouter lists it, with prices from the providers that serve it.
- What OpenRouter says: Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters). It performs strongly in software engineering and professional...

## Models (1)

| Model | OpenRouter id | Released | Context | Input $/1M | Output $/1M | Supports |
| --- | --- | --- | --- | --- | --- | --- |
| Step 5 Preview | `stepfun/step-5-preview` | 2026-10 | 1M | $1 | $2.70 | tools, structured output, reasoning, caching, image, video |

Prices and limits as OpenRouter lists them; a provider's own price can differ.

- JSON: https://www.anchorterminal.com/api/v1/tools/step.json
- Being indexed says nothing about quality, and nobody can pay for it. Ask for a review: https://www.anchorterminal.com/builders/#claiming