Compare GPT Chat from OpenAI and Grok 4.5 from Grok on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
GPT Chat
Grok 4.5GPT Chat Latest points to OpenAI's stable API alias chat-latest that always resolves to the latest Instant chat model used in ChatGPT. As OpenAI rolls out new Instant model updates in the future, they are routed behind this slug automatically.
Grok 4.5 was trained on datasets spanning knowledge in coding, science, engineering, and math. With both intelligent and efficient reasoning, Grok 4.5 excels at real engineering tasks and exceeds comparable leading models at these tasks.
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.
Grok 4.5: $6.00/M output tokens; GPT Chat: $30.00/M. Use the cost calculator above to estimate your own workload.
Grok 4.5: 1.5s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
GPT Chat accepts 1,050,000 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 128,000 tokens on GPT Chat and 500,000 tokens on Grok 4.5.
GPT Chat at 71.8 tok/s and Grok 4.5 at 25.5 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
GPT Chat accepts text and image input and supports thinking, function calling, structured outputs, web search and tool calling; Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context.
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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