Claude Opus 4.5 does not enable reasoning mode by default. To access its deep reasoning capabilities, users would typically need to call the native Claude API. To make this capability available through an OpenAI-compatible interface, we provide the claude-opus-4-5-think model, which has reasoning mode pre-enabled and a default 32k-token context window, allowing it to be called directly via the OpenAI unified API. Claude Opus 4.5 Think is a reasoning-focused variant of Claude Opus 4.5 designed for advanced tasks that require rigorous reasoning, complex decision-making, and long-chain analysis. Aside from its enhanced reasoning mechanism, all other capabilities remain consistent with the standard Claude Opus 4.5 model, making it well suited for complex engineering problem decomposition, multi-stage planning, and logic-intensive analysis.
Claude Opus 4.5 Thinking vs Kimi K3
Compare Claude Opus 4.5 Thinking from Anthropic and Kimi K3 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.
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.
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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 (%)
LMArena Benchmarks
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.
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: Claude Opus 4.5 Thinking, Kimi K3?
Kimi K3: $15.00/M output tokens; Claude Opus 4.5 Thinking: $25.00/M. Use the cost calculator above to estimate your own workload.
How do their coding arena scores compare?
Kimi K3: 1531; Claude Opus 4.5 Thinking: 1530 (LMArena coding leaderboard).
How large is each context window?
Claude Opus 4.5 Thinking accepts 200,000 and Kimi K3 accepts 1,048,576 input tokens. Maximum output per request is 32,000 tokens on Claude Opus 4.5 Thinking and 1,048,576 tokens on Kimi K3.
What inputs and capabilities does each model support?
Claude Opus 4.5 Thinking accepts image and text 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 Claude Opus 4.5 Thinking 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.
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