Models

Grok 4.5 vs Kimi K2 Instruct

Compare Grok 4.5 from Grok and Kimi K2 Instruct from Moonshot AI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.

GrokGrok 4.5Moonshot AIKimi K2 Instruct
Grok logo
Grok 4.5
Grok · text, image → text

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.

Input$2.00 /M
Output$6.00 /M
Moonshot AI logo
Kimi K2 Instruct
Moonshot AI · text → text

Kimi-K2 is a MoE architecture foundational model with extremely powerful coding and agent capabilities, featuring a total of 1 trillion parameters and activating 32 billion parameters. In benchmark performance tests across major categories such as general knowledge reasoning, programming, mathematics, and agents, the K2 model outperforms other mainstream open-source models. The Kimi-K2 model supports a context length of 128k tokens. It does not support visual capabilities.

Input$0.54 /M
Output$2.16 /M

Pricing & Specifications

Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.

Grok 4.5
Kimi K2 Instruct
Input /M
$2.00
$0.54
Output /M
$6.00
$2.16
Cache read /M
$0.50
$0.54
Context length
500,000
0
Max output
500,000
0
Time to First Token
1.5 s
0.1 s
Throughput
25.6 tok/s
40.0 tok/s
Modalities
textimage
text
Supported Parameters
thinkingtoolsfunction callingstructured outputslong context
toolsfunction callingstructured outputs
API Formats
Released
July 2026
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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.

grok-4.5kimi-k2-instruct

Tokens / day

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Requests / day

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Performance Past 3 Days

Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.

grok-4.5kimi-k2-instruct

Throughput (tok/s)

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TTFT (s)

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Uptime (%)

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LMArena Benchmarks

LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.

Text
grok-4.5kimi-k2-instruct
1360142014801540
Overall
14181470
Coding
14671523
Math
14161478
Hard prompts
14371495
Instruction following
13901466
Multi-turn
14041477
Creative writing
13821449
Longer query
14031485
Chinese
14541511
English
14231475

Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.

Cost calculator

Estimate your monthly bill for the same workload on each model.

Kimi K2 Instruct
$64.80 /mo
Grok 4.5
$210 /mo

Monthly = daily × 30. Discounted rates applied where a promotion is active.

FAQ

Which is cheaper: Grok 4.5, Kimi K2 Instruct?

Kimi K2 Instruct: $2.16/M output tokens; Grok 4.5: $6.00/M. Use the cost calculator above to estimate your own workload.

How do their coding arena scores compare?

Grok 4.5: 1523; Kimi K2 Instruct: 1467 (LMArena coding leaderboard).

Which responds faster?

Kimi K2 Instruct: 0.1s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.

Which one generates tokens faster?

Kimi K2 Instruct at 40.0 tok/s and Grok 4.5 at 25.6 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 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context; Kimi K2 Instruct accepts text input and supports tool calling, function calling and structured outputs.

Can I call Grok 4.5 and Kimi K2 Instruct 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.

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