Compare Kimi K3 from Moonshot AI and Step 5 Preview from StepFun on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Kimi K3
Step 5 PreviewKimi K3 is Kimi’s flagship model for long-horizon coding and end-to-end knowledge work, with a 1M-token context window and industry-leading intelligence.
Step 5 Preview is StepFun's next-generation flagship base model designed for real-world tasks, with a focus on programming and professional expertise.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
Step 5 Preview: $3.0888/M output tokens; Kimi K3: $13.5/M. Use the cost calculator above to estimate your own workload.
Kimi K3 accepts 1,048,576 and Step 5 Preview accepts 256,000 input tokens.
Kimi K3 accepts text, image and video input and supports thinking, function calling and structured outputs; Step 5 Preview accepts text, image and video input.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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