Output tokens cost $6.00 per million on Grok 4.20 Beta 0309 (reasoning) and $15.00 per million on Kimi K3. Input tokens cost $2.00 per million on Grok 4.20 Beta 0309 (reasoning) and $3.00 per million on Kimi K3. Cached input tokens are billed at $0.20 per million on Grok 4.20 Beta 0309 (reasoning) and $0.30 per million on Kimi K3. Context lengths are 2,000,000 tokens on Grok 4.20 Beta 0309 (reasoning) and 1,048,576 tokens on Kimi K3. Time to first token (TTFT) measured on AIHubMix is 1.7s on Grok 4.20 Beta 0309 (reasoning) and 0.9s on Kimi K3. Measured output throughput is 74.3 tok/s on Grok 4.20 Beta 0309 (reasoning) and 73.1 tok/s on Kimi K3. On the LMArena coding leaderboard Grok 4.20 Beta 0309 (reasoning) scores 1511 and Kimi K3 scores 1531.
Grok 4.20 Beta 0309 (reasoning)
Kimi K3Grok 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.
Kimi K3 is Kimi’s flagship model for long-horizon coding and end-to-end knowledge work, with a 1M-token context window and industry-leading intelligence.
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): $6.00/M output tokens; Kimi K3: $15.00/M. Use the cost calculator above to estimate your own workload.
Kimi K3: 1531; Grok 4.20 Beta 0309 (reasoning): 1511 (LMArena coding leaderboard).
Kimi K3: 0.9s 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 Kimi K3 accepts 1,048,576 input tokens. Maximum output per request is 2,000,000 tokens on Grok 4.20 Beta 0309 (reasoning) and 1,048,576 tokens on Kimi K3.
Grok 4.20 Beta 0309 (reasoning) at 74.3 tok/s and Kimi K3 at 73.1 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; Kimi K3 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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