GPT-5.6 Terra (Low) vs GPT-6 Luna (Xhigh)
Which is better for the money: GPT-5.6 Terra (Low) 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 (Low): 25.8% more intelligence, 80.9% less cost to run the AA benchmark, and 377.0% slower end-to-end.
| Metric | GPT-5.6 Terra (Low) | GPT-6 Luna (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 27.5 | 34.6 | +25.8% GPT-6 Luna (Xhigh) is 25.8% more intelligent |
| Total AA cost (lower is better) | $350.36 | $66.81 | −80.9% GPT-6 Luna (Xhigh) is 80.9% cheaper |
| End-to-end time (lower is better) | 5.73s | 27.33s | +377.0% GPT-6 Luna (Xhigh) is 377.0% 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 (Low) is off the frontier: at the same or lower cost, MiMo-V2.6-Pro scores 46.30 for $207.
- GPT-6 Luna (Xhigh) is on today's frontier: nothing is both smarter and cheaper.
GPT-5.6 Terra (Low)GPT-6 Luna (Xhigh)Today's Pareto frontierEvery other model
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gpt-5-6-terra-low/gpt-6-luna-xhigh · Markdown: /api/v1/compare/gpt-5-6-terra-low/gpt-6-luna-xhigh?format=md · llms.txt · agent skill