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Step 5 Preview

Auto-discovered from the NVIDIA catalog on 2026-10-17.

stepfun-ai/step-5-preview
Running· verified 20 min ago · 492ms

What is Step 5 Preview?

Step 5 Preview is StepFun's reasoning model. Auto-discovered from the NVIDIA catalog on 2026-10-17. It runs on Speka's OpenAI-compatible /v1/chat/completions endpoint at $0.20 / 1M input and $0.20 / 1M output tokens, using the model ID stepfun-ai/step-5-preview.

Test it live

Live playgroundStep 5 Previewin-browser demo

Test Step 5 Preview live

Send a message and watch the model respond. Multi-turn — it remembers the conversation.

How to call Step 5 Preview via the API

Speka exposes Step 5 Preview on an OpenAI-compatible /v1/chat/completions endpoint. Point any OpenAI SDK at https://speka.me/v1, set model to stepfun-ai/step-5-preview, and your existing code runs unchanged.

quickstart.py
from openai import OpenAI

client = OpenAI(
    base_url="https://speka.me/v1",
    api_key="sk-speka-live-...",  # your Speka key
)

resp = client.chat.completions.create(
    model="stepfun-ai/step-5-preview",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(resp.choices[0].message.content)
FAQ

Frequently asked questions

Step 5 Preview is StepFun's reasoning model. Auto-discovered from the NVIDIA catalog on 2026-10-17. It is available on Speka's OpenAI-compatible API using the model ID stepfun-ai/step-5-preview.
On Speka, Step 5 Preview is priced at $0.20 / 1M input and $0.20 / 1M output tokens. Pricing is per-token with no subscription or seat fee — usage is billed against your plan's monthly allowance, then at the same rate with no overage penalty. Rates are current as of June 2026; check the pricing page for updates.
Speka exposes Step 5 Preview on an OpenAI-compatible /v1/chat/completions endpoint. Set base_url to https://speka.me/v1, supply your Speka key, and set model to "stepfun-ai/step-5-preview" in any OpenAI SDK — no other code changes are required.
Yes. Step 5 Preview is served through Speka's OpenAI-compatible endpoint, so any application built on the OpenAI Python or Node.js SDK, LangChain, or LlamaIndex can call it by changing only the base URL and model ID.

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