Output tokens cost $6.00 per million on Grok 4.5 and $2.19 per million on Kimi K2 Thinking. Input tokens cost $2.00 per million on Grok 4.5 and $0.55 per million on Kimi K2 Thinking. Cached input tokens are billed at $0.50 per million on Grok 4.5 and $0.14 per million on Kimi K2 Thinking. Context lengths are 500,000 tokens on Grok 4.5 and 262,144 tokens on Kimi K2 Thinking. Time to first token (TTFT) measured on AIHubMix is 2.2s on Grok 4.5 and 0.4s on Kimi K2 Thinking. Measured output throughput is 27.1 tok/s on Grok 4.5 and 208.3 tok/s on Kimi K2 Thinking. On the LMArena coding leaderboard Grok 4.5 scores 1523 and Kimi K2 Thinking scores 1467.
Grok 4.5
Kimi K2 ThinkingGrok 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 Thinking is Moonshot AI's most advanced open-source inference model to date, extending the K2 series into intelligent agent and long-context inference domains. The model is built on the trillion-parameter mixture of experts (MoE) architecture introduced by Kimi K2, activating 32 billion parameters per forward pass and supporting a context window of 256,000 tokens.
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 Thinking: $2.19/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 Thinking: 1467 (LMArena coding leaderboard).
Kimi K2 Thinking: 0.4s 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 Thinking accepts 262,144 input tokens. Maximum output per request is 500,000 tokens on Grok 4.5 and 262,144 tokens on Kimi K2 Thinking.
Kimi K2 Thinking at 208.3 tok/s and Grok 4.5 at 27.1 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 Thinking accepts text input and supports thinking, tool calling, 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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