GPT-5.6 Terra (Low) vs GPT-6 Luna (Medium)
Which is better for the money: GPT-5.6 Terra (Low) by OpenAI or GPT-6 Luna (Medium) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Clear winner
Verdict
Pick GPT-6 Luna (Medium)
GPT-6 Luna (Medium) vs GPT-5.6 Terra (Low): 8.7% more intelligence, 91.1% less cost to run the AA benchmark, and end-to-end time not fully reported.
| Metric | GPT-5.6 Terra (Low) | GPT-6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 27.5 | 29.9 | +8.7% GPT-6 Luna (Medium) is 8.7% more intelligent |
| Total AA cost (lower is better) | $350.36 | $31.17 | −91.1% GPT-6 Luna (Medium) is 91.1% cheaper |
| End-to-end time (lower is better) | 5.91s | Not reported | — not comparable |
| 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 (Medium) is on today's frontier: nothing is both smarter and cheaper.
GPT-5.6 Terra (Low)GPT-6 Luna (Medium)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-medium · Markdown: /api/v1/compare/gpt-5-6-terra-low/gpt-6-luna-medium?format=md · llms.txt · agent skill