Compare Grok 4.5 from Grok and Union Alpha (free) from Stealth on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Grok 4.5
Union Alpha (free)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.
Developed by Stealth, Union Alpha is a multimodal model built for research, coding, and agentic workflows. It delivers frontier-level performance across a broad range of general-purpose tasks. Featuring a massive 262,144 token context window, this model is highly capable of handling extensive and complex 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.
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Grok 4.5 accepts 500,000 and Union Alpha (free) accepts 262,144 input tokens.
Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context; Union Alpha (free) accepts text and image input.
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