Output tokens cost $6.00 per million on Grok 4.5 and $3.00 per million on Kimi K2.5. Input tokens cost $2.00 per million on Grok 4.5 and $0.60 per million on Kimi K2.5. Cached input tokens are billed at $0.50 per million on Grok 4.5 and $0.11 per million on Kimi K2.5. Context lengths are 500,000 tokens on Grok 4.5 and 256,000 tokens on Kimi K2.5. Time to first token (TTFT) measured on AIHubMix is 1.9s on Grok 4.5 and 1.1s on Kimi K2.5. Measured output throughput is 26.6 tok/s on Grok 4.5 and 32.1 tok/s on Kimi K2.5. On the LMArena coding leaderboard Grok 4.5 scores 1523 and Kimi K2.5 scores 1501.
Grok 4.5
Kimi K2.5Grok 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.
Kimi K2.5 is the smartest model of Kimi to date, achieving open-source state-of-the-art (SoTA) performance in Agent, coding, visual understanding, and a series of general intelligent tasks. At the same time, Kimi K2.5 is also the most versatile model of Kimi so far, with a native multimodal architecture design that supports both visual and text input, thinking and non-thinking modes, as well as dialogue and Agent 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.
Kimi K2.5: $3.00/M output tokens; Grok 4.5: $6.00/M. Use the cost calculator above to estimate your own workload.
Grok 4.5: 1523; Kimi K2.5: 1501 (LMArena coding leaderboard).
Kimi K2.5: 1.1s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Grok 4.5 accepts 500,000 and Kimi K2.5 accepts 256,000 input tokens.
Kimi K2.5 at 32.1 tok/s and Grok 4.5 at 26.6 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context; Kimi K2.5 accepts text, image and video input and supports thinking, function calling and structured outputs.
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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