GPT-5.6 Luna (Medium) vs GPT-5.6 Terra (Medium)
Which is better for the money: GPT-5.6 Luna (Medium) 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 2026-10-26.
Trade-off
Verdict
Depends on your budget
GPT-5.6 Terra (Medium) scores 5.1 points higher (30.1 vs 25.0) but costs 10× as much to run the benchmark ($447 vs $44.3; mid-range vs budget cost classes). They are not alternatives at one budget: pick GPT-5.6 Terra (Medium) 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-5.6 Terra (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 25.0 | 30.1 | +20.4% GPT-5.6 Terra (Medium) is 20.4% more intelligent |
| Total AA cost (lower is better) | $44.32 | $446.53 | +907.5% GPT-5.6 Terra (Medium) is 10× more expensive |
| End-to-end time (lower is better) | 6.64s | 5.99s | −9.8% GPT-5.6 Terra (Medium) is 9.8% faster |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Terra (Medium) vs GPT-5.6 Luna (Medium): 20.4% more intelligence, 907.5% more cost to run the AA benchmark, and 9.8% 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-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 (Medium)GPT-5.6 Terra (Medium)Today's Pareto frontierEvery other model
Matchup
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