StepFun

Step 5 Preview API

CN StepFun | released 2026-10
Try in Playground → Get API key

Step 5 Preview is StepFun’s new-generation flagship base model for real-world tasks, focused on programming and professional knowledge work. It natively accepts text, image and video input, making it a versatile single model for multimodal understanding at frontier quality.

visionCodeReasoningFlagship

Pricing (official list, per 1M tokens)

Input
$1.04/M
Output
$2.98/M

Specifications

Context window256K tokens Input modalitiesText StreamingYes APIOpenAI-compatible

How to use Step 5 Preview

Drop-in OpenAI replacement. Change only the base_url and model.

# Python -pip install openai
from openai import OpenAI

client = OpenAI(
    base_url="https://meshtok.com/v1",
    api_key="sk-your-MeshTok-key",
)

resp = client.chat.completions.create(
    model="stepfun/step-5-preview",
    messages=[{"role":"user","content":"Hello!"}],
)
print(resp.choices[0].message.content)
# cURL
curl https://meshtok.com/v1/chat/completions \
  -H "Authorization: Bearer sk-your-MeshTok-key" \
  -H "Content-Type: application/json" \
  -d '{"model":"stepfun/step-5-preview","messages":[{"role":"user","content":"Hello!"}]}'

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