Grok 4.1 is a new conversational model with significant improvements in real-world usability, delivering exceptional performance in creative, emotional, and collaborative interactions. It is more perceptive to nuanced user intent, more engaging to converse with, and more coherent in personality, while fully preserving its core intelligence and reliability. Built on large-scale reinforcement learning infrastructure, the model is optimized for style, personality, helpfulness, and alignment, and leverages frontier agentic reasoning models as reward evaluators to autonomously assess and iterate on responses at scale, significantly enhancing overall interaction quality.
Grok Code Fast 1 vs Kimi K3
Output tokens cost $0.50 per million on Grok Code Fast 1 and $15.00 per million on Kimi K3. Input tokens cost $0.20 per million on Grok Code Fast 1 and $3.00 per million on Kimi K3. Cached input tokens are billed at $0.05 per million on Grok Code Fast 1 and $0.30 per million on Kimi K3. Context lengths are 256,000 tokens on Grok Code Fast 1 and 1,048,576 tokens on Kimi K3. Time to first token (TTFT) measured on AIHubMix is 1.3s on Grok Code Fast 1 and 0.9s on Kimi K3. Measured output throughput is 87.0 tok/s on Grok Code Fast 1 and 73.1 tok/s on Kimi K3.
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.
Pricing & Specifications
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.
Activity Past 30 Days
Daily traffic served through AIHubMix — how demand for each model is trending.
Tokens / day
Requests / day
Performance Past 3 Days
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Throughput (tok/s)
TTFT (s)
Uptime (%)
Cost calculator
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which is cheaper: Grok Code Fast 1, Kimi K3?
Grok Code Fast 1: $0.50/M output tokens; Kimi K3: $15.00/M. Use the cost calculator above to estimate your own workload.
Which responds faster?
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.
How large is each context window?
Grok Code Fast 1 accepts 256,000 and Kimi K3 accepts 1,048,576 input tokens. Maximum output per request is 10,000 tokens on Grok Code Fast 1 and 1,048,576 tokens on Kimi K3.
Which one generates tokens faster?
Grok Code Fast 1 at 87.0 tok/s and Kimi K3 at 73.1 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
What inputs and capabilities does each model support?
Grok Code Fast 1 accepts text and image input and supports thinking, tool calling, function calling and structured outputs; Kimi K3 accepts text, image and video input and supports thinking, function calling and structured outputs.
Can I call Grok Code Fast 1 and Kimi K3 with the same API key?
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.
Popular comparisons
Related model match-ups readers also look at.
