Compare Grok 4.20 Beta 0309 (reasoning) from Grok 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.
Grok 4.20 Beta 0309 (reasoning)Grok 4.5Grok 4.20 Beta is our latest flagship model, offering industry-leading speed and agent tool-invocation capabilities. It combines the lowest hallucination rate on the market with strict prompt adherence, enabling it to consistently deliver precise and factual responses.
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.
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
Grok 4.20 Beta 0309 (reasoning): $6/M output tokens; Grok 4.5: $6/M. Use the cost calculator above to estimate your own workload.
Grok 4.5: 1523; Grok 4.20 Beta 0309 (reasoning): 1510 (LMArena coding leaderboard).
Grok 4.20 Beta 0309 (reasoning): 1.7s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Grok 4.20 Beta 0309 (reasoning) accepts 2,000,000 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 2,000,000 tokens on Grok 4.20 Beta 0309 (reasoning) and 500,000 tokens on Grok 4.5.
Grok 4.20 Beta 0309 (reasoning) at 74.3 tok/s and Grok 4.5 at 31.5 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
Grok 4.20 Beta 0309 (reasoning) accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context; Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context.
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