GPT-5.6 Terra (High) vs GPT-6 Luna (Xhigh)
Which is better for the money: GPT-5.6 Terra (High) by OpenAI or GPT-6 Luna (Xhigh) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Clear winner
Verdict
Pick GPT-6 Luna (Xhigh)
GPT-6 Luna (Xhigh) vs GPT-5.6 Terra (High): 1.2% more intelligence, 91.3% less cost to run the AA benchmark, and 274.4% slower end-to-end.
| Metric | GPT-5.6 Terra (High) | GPT-6 Luna (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 34.2 | 34.6 | +1.2% GPT-6 Luna (Xhigh) is 1.2% more intelligent |
| Total AA cost (lower is better) | $767.78 | $66.81 | −91.3% GPT-6 Luna (Xhigh) is 91.3% cheaper |
| End-to-end time (lower is better) | 7.30s | 27.33s | +274.4% GPT-6 Luna (Xhigh) is 274.4% slower |
| Price per 1M tokens (in / out) | $2.00 / $12.0 | $0.10 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
Today's Pareto frontier
Against the frontier
- GPT-5.6 Terra (High) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- GPT-6 Luna (Xhigh) is on today's frontier: nothing is both smarter and cheaper.
GPT-5.6 Terra (High)GPT-6 Luna (Xhigh)Today's Pareto frontierEvery other model
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