GPT-5.2 pro is available in the Responses API only to enable support for multi-turn model interactions before responding to API requests, and other advanced API features in the future. Since GPT-5.2 pro is designed to tackle tough problems, some requests may take several minutes to finish. To avoid timeouts, try using background mode. GPT-5.2 pro supports reasoning.effort: medium, high, xhigh.
GPT 5.2 Pro vs GPT 5.6 Luna
Compare GPT 5.2 Pro from OpenAI 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: GPT 5.2 Pro, GPT 5.6 Luna?
GPT 5.6 Luna: $6/M output tokens; GPT 5.2 Pro: $168/M. Use the cost calculator above to estimate your own workload.
How large is each context window?
GPT 5.2 Pro accepts 400,000 and GPT 5.6 Luna accepts 1,050,000 input tokens. Maximum output per request is 128,000 tokens on GPT 5.2 Pro and 128,000 tokens on GPT 5.6 Luna.
What inputs and capabilities does each model support?
GPT 5.2 Pro accepts text and image input and supports thinking, web search, 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 GPT 5.2 Pro 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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