GPT-5.6 Luna (Low) vs GPT-6 Luna (Xhigh)
Which is better for the money: GPT-5.6 Luna (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.
Trade-off
Verdict
Depends on your budget
GPT-6 Luna (Xhigh) scores 13.6 points higher (34.6 vs 21.0) but costs 2.5× as much to run the benchmark ($66.8 vs $27.0; mid-range vs budget cost classes). Pick GPT-6 Luna (Xhigh) when the extra intelligence is worth the premium, otherwise GPT-5.6 Luna (Low).
| Metric | GPT-5.6 Luna (Low) | GPT-6 Luna (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 21.0 | 34.6 | +64.8% GPT-6 Luna (Xhigh) is 64.8% more intelligent |
| Total AA cost (lower is better) | $27.02 | $66.81 | +147.3% GPT-6 Luna (Xhigh) is 2.5× more expensive |
| End-to-end time (lower is better) | 5.68s | 28.14s | +395.4% GPT-6 Luna (Xhigh) is 395.4% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $0.10 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
GPT-6 Luna (Xhigh) vs GPT-5.6 Luna (Low): 64.8% more intelligence, 147.3% more cost to run the AA benchmark, and 395.4% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Low) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
- GPT-6 Luna (Xhigh) is on today's frontier: nothing is both smarter and cheaper.
GPT-5.6 Luna (Low)GPT-6 Luna (Xhigh)Today's Pareto frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gpt-5-6-luna-low/gpt-6-luna-xhigh · Markdown: /api/v1/compare/gpt-5-6-luna-low/gpt-6-luna-xhigh?format=md · llms.txt · agent skill