Compare GPT 6 Astra 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 6 Astra
Grok 4.5GPT-6 Astra is OpenAI's newest and most intelligent model, with industry-leading performance in computer operations, web browsing, software engineering, scientific research, and professional work. It excels at executing multi-step workflows across code, browsers, and various professional software. Astra can achieve better results with significantly fewer output tokens, making its estimated API cost per task lower.
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/M output tokens; GPT 6 Astra: $50/M. Use the cost calculator above to estimate your own workload.
Grok 4.5: 5.6s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
GPT 6 Astra accepts 1,050,000 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 128,000 tokens on GPT 6 Astra and 500,000 tokens on Grok 4.5.
GPT 6 Astra at 42.2 tok/s and Grok 4.5 at 28.6 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
GPT 6 Astra accepts text and image input and supports tool calling, thinking and structured outputs; Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context.
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