Claude Sonnet 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, the claude-sonnet-4-5-think model is provided with reasoning mode pre-enabled and a default 64k-token context window, allowing it to be called directly via the OpenAI unified API. Claude Sonnet 4.5 Think is a reasoning-focused variant of Claude Sonnet 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 Sonnet 4.5 model, making it well suited for complex problem decomposition, multi-step planning, and logic-intensive analysis.
Claude Sonnet 4.5 Thinking vs GPT 5.6 Luna
Compare Claude Sonnet 4.5 Thinking from Anthropic and GPT 5.6 Luna from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
GPT-5.6 Luna is designed for cost-sensitive, high-volume workloads. It roughly corresponds to the nano model tier used in earlier GPT-5 families.
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: Claude Sonnet 4.5 Thinking, GPT 5.6 Luna?
GPT 5.6 Luna: $1.2/M output tokens; Claude Sonnet 4.5 Thinking: $16.5/M. Use the cost calculator above to estimate your own workload.
Which responds faster?
Claude Sonnet 4.5 Thinking: 1.6s 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?
Claude Sonnet 4.5 Thinking accepts 200,000 and GPT 5.6 Luna accepts 1,050,000 input tokens. Maximum output per request is 64,000 tokens on Claude Sonnet 4.5 Thinking and 128,000 tokens on GPT 5.6 Luna.
Which one generates tokens faster?
Claude Sonnet 4.5 Thinking at 60.2 tok/s and GPT 5.6 Luna at 47.6 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
What inputs and capabilities does each model support?
Claude Sonnet 4.5 Thinking accepts text, image and PDF input and supports thinking, tool calling, function calling and structured outputs; GPT 5.6 Luna accepts text and image input and supports tool calling, thinking and structured outputs.
Can I call Claude Sonnet 4.5 Thinking and GPT 5.6 Luna 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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