GPT-5.6 Luna (Xhigh) vs GPT-5.6 Terra (Medium)
Which is better for the money: GPT-5.6 Luna (Xhigh) by OpenAI or GPT-5.6 Terra (Medium) 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-5.6 Luna (Xhigh)
GPT-5.6 Terra (Medium) vs GPT-5.6 Luna (Xhigh): 13.0% less intelligence, 149.0% more cost to run the AA benchmark, and 85.7% faster end-to-end.
| Metric | GPT-5.6 Luna (Xhigh) | GPT-5.6 Terra (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 34.6 | 30.1 | −13.0% GPT-5.6 Terra (Medium) is 13.0% less intelligent |
| Total AA cost (lower is better) | $179.33 | $446.53 | +149.0% GPT-5.6 Terra (Medium) is 2.5× more expensive |
| End-to-end time (lower is better) | 39.18s | 5.59s | −85.7% GPT-5.6 Terra (Medium) is 85.7% faster |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Xhigh) is off the frontier: at the same or lower cost, GPT-6.1 Terra (Medium) scores 41.30 for $175.
- GPT-5.6 Terra (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Medium) scores 47.80 for $361.
GPT-5.6 Luna (Xhigh)GPT-5.6 Terra (Medium)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-xhigh/gpt-5-6-terra-medium · Markdown: /api/v1/compare/gpt-5-6-luna-xhigh/gpt-5-6-terra-medium?format=md · llms.txt · agent skill