Models

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.

AnthropicClaude Sonnet 4.5 ThinkingOpenAIGPT 5.6 Luna
Anthropic logo
Claude Sonnet 4.5 Thinking
Anthropic · text, image, pdf → text

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.

Input$3.3 /M
Output$16.5 /M
OpenAI logo
GPT 5.6 Luna
OpenAI · text, image → text

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.

Input$0.2 /M
Output$1.2 /M
Cache read$0.02 /M

Pricing & Specifications

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

Claude Sonnet 4.5 Thinking
GPT 5.6 Luna
Input /M
$3.3
$0.2
Output /M
$16.5
$1.2
Cache read /M
-
$0.02
Context length
200,000
1,050,000
Max output
64,000
128,000
Time to First Token
1.6 s
5.0 s
Throughput
60.2 tok/s
47.6 tok/s
Modalities
textimagepdf
textimage
Supported Parameters
thinkingtoolsfunction callingstructured outputs
toolsthinkingstructured outputs
API Formats
chat_completions · responses
Released
September 29, 2025
July 9, 2026

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.

claude-sonnet-4-5-thinkgpt-5.6-luna

Tokens / day

-

Requests / day

-

Performance Past 3 Days

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

claude-sonnet-4-5-thinkgpt-5.6-luna

Throughput (tok/s)

-

TTFT (s)

-

Uptime (%)

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Cost calculator

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

GPT 5.6 Luna
$30.00 /mo
Claude Sonnet 4.5 Thinking
$446 /mo

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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