Compare GPT 4o 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 4oGPT 5.6 LunaThe stable multimodal model from OpenAI, with the official designated version being gpt-4o-2024-08-06; our site supports the official automatic caching, and charges for hits on some parts will be automatically halved.
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.
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.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
GPT 5.6 Luna: $6/M output tokens; GPT 4o: $10/M. Use the cost calculator above to estimate your own workload.
GPT 4o: 0.6s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
GPT 4o accepts 128,000 and GPT 5.6 Luna accepts 1,050,000 input tokens. Maximum output per request is 16,384 tokens on GPT 4o and 128,000 tokens on GPT 5.6 Luna.
GPT 5.6 Luna at 88.4 tok/s and GPT 4o at 52.2 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
GPT 4o accepts text, image and PDF input and supports tool calling, function calling and structured outputs; GPT 5.6 Luna accepts text and image input and supports tool calling, thinking and structured outputs.
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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