Skip to content
  • Models
  • Rankings
  • Ori
Sign Up
Sign Up
OpenRouterOpenRouter
© 2026 OpenRouter, Inc

Product

  • Chat
  • Rankings
  • Benchmarks
  • Apps
  • Discover
  • Models
  • Collections
  • Providers
  • Tools
  • Pricing
  • Business
  • Enterprise
  • Labs

Company

  • About
  • Blog
  • Careers
    Hiring
  • Privacy
  • Terms of Service
  • Trust Center
  • Support
  • Works With OR
  • Data
  • Brand

Developer

  • Documentation
  • API Reference
  • Developer Platform
  • Status
  • AI Site Map

Connect

  • Discord
  • GitHub
  • LinkedIn
  • X
  • YouTube
Favicon for stepfun-ai

Stepfun AI

Access 1 Stepfun AI model through the OpenRouter unified API including Step3. Compare pricing, context windows, benchmarks, and capabilities between different Stepfun AI models.

Stepfun AI requests made on OpenRouter

Not enough data to display yet.

  • Favicon for stepfun-ai
    StepFun: Step3Step3

    Step3 is a cutting-edge multimodal reasoning model—built on a Mixture-of-Experts architecture with 321B total parameters and 38B active. It is designed end-to-end to minimize decoding costs while delivering top-tier performance in vision–language reasoning. Through the co-design of Multi-Matrix Factorization Attention (MFA) and Attention-FFN Disaggregation (AFD), Step3 maintains exceptional efficiency across both flagship and low-end accelerators.

    by stepfun-aiAug 28, 202566K context

Frequently asked questions

OpenRouter serves 1 Stepfun AI model behind one OpenAI-compatible API. Create an OpenRouter API key, point your client at https://openrouter.ai/api/v1, and set the model to an ID such as stepfun-ai/step3. The quickstart has request examples for every supported SDK.

Step3 has the largest context window of any Stepfun AI model on OpenRouter, accepting up to 65,536 tokens per request.

Step3 is the most recently added Stepfun AI model on OpenRouter, listed on August 28, 2025.