GPT-5.6 Luna (Medium) vs GPT-6.1 Terra (Non-reasoning)
Which is better for the money: GPT-5.6 Luna (Medium) by OpenAI or GPT-6.1 Terra (Non-reasoning) 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-6.1 Terra (Non-reasoning) scores 8.5 points higher (33.5 vs 25.0) but costs 3.5× as much to run the benchmark ($154 vs $44.3; mid-range vs budget cost classes). They are not alternatives at one budget: pick GPT-6.1 Terra (Non-reasoning) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | GPT-5.6 Luna (Medium) | GPT-6.1 Terra (Non-reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 25.0 | 33.5 | +34.0% GPT-6.1 Terra (Non-re… is 34.0% more intelligent |
| Total AA cost (lower is better) | $44.32 | $153.58 | +246.5% GPT-6.1 Terra (Non-re… is 3.5× more expensive |
| End-to-end time (lower is better) | 6.65s | 6.61s | −0.6% GPT-6.1 Terra (Non-re… is 0.6% faster |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $1.00 / $5.00 | |
| Input modalities | Text, Image | Text, Image |
GPT-6.1 Terra (Non-reasoning) vs GPT-5.6 Luna (Medium): 34.0% more intelligence, 246.5% more cost to run the AA benchmark, and 0.6% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Medium) is off the frontier: at the same or lower cost, GPT-6 Luna (Medium) scores 29.90 for $31.2.
- GPT-6.1 Terra (Non-reasoning) is off the frontier: at the same or lower cost, GPT-6 Luna (Max) scores 38.10 for $122.
GPT-5.6 Luna (Medium)GPT-6.1 Terra (Non-reasoning)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-medium/gpt-6-1-terra-non-reasoning · Markdown: /api/v1/compare/gpt-5-6-luna-medium/gpt-6-1-terra-non-reasoning?format=md · llms.txt · agent skill