Phi-4-Reasoning is a state-of-the-art open-weight reasoning model finetuned from Phi-4 using supervised fine-tuning on a dataset of chain-of-thought traces and reinforcement learning. The supervised fine-tuning dataset includes a blend of synthetic prompts and high-quality filtered data from public domain websites, focused on math, science, and coding skills as well as alignment data for safety and Responsible AI. The goal of this approach was to ensure that small capable models were trained with data focused on high quality and advanced reasoning.
AIHubMix Phi 4 (reasoning) vs Step 3.7 Flash
Compare AIHubMix Phi 4 (reasoning) from Microsoft and Step 3.7 Flash 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.
step-3.7-flash is stepfun's flagship inference model, designed for high-complexity tasks that require deep reasoning and fast execution. It excels at decomposing multi-step problems, performing tool calls, and maintaining consistency across massive datasets. It is the preferred choice for complex workloads such as long-context agents, advanced software engineering, and end-to-end research automation.
Pricing & Specifications
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.
Activity Past 30 Days
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Performance Past 3 Days
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Cost calculator
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FAQ
Which is cheaper: AIHubMix Phi 4 (reasoning), Step 3.7 Flash?
AIHubMix Phi 4 (reasoning): $0.2/M output tokens; Step 3.7 Flash: $1.32/M. Use the cost calculator above to estimate your own workload.
How large is each context window?
AIHubMix Phi 4 (reasoning) accepts 128,000 and Step 3.7 Flash accepts 256,000 input tokens.
What inputs and capabilities does each model support?
AIHubMix Phi 4 (reasoning) accepts text input and supports thinking; Step 3.7 Flash accepts text, image and video input.
Can I call AIHubMix Phi 4 (reasoning) and Step 3.7 Flash with the same API key?
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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