GPT-5.6 Luna (High) vs GPT-6.1 Terra (Medium)
Which is better for the money: GPT-5.6 Luna (High) by OpenAI or GPT-6.1 Terra (Medium) 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 (Medium) scores 9.2 points higher (41.3 vs 32.1) but costs 1.6× as much to run the benchmark ($175 vs $108; both mid-range class). Pick GPT-6.1 Terra (Medium) when the extra intelligence is worth the premium, otherwise GPT-5.6 Luna (High).
| Metric | GPT-5.6 Luna (High) | GPT-6.1 Terra (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 32.1 | 41.3 | +28.7% GPT-6.1 Terra (Medium) is 28.7% more intelligent |
| Total AA cost (lower is better) | $108.15 | $175.20 | +62.0% GPT-6.1 Terra (Medium) is 62.0% more expensive |
| End-to-end time (lower is better) | 16.30s | 6.95s | −57.4% GPT-6.1 Terra (Medium) is 57.4% 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 (Medium) vs GPT-5.6 Luna (High): 28.7% more intelligence, 62.0% more cost to run the AA benchmark, and 57.4% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (High) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (High) scores 37.80 for $94.1.
- GPT-6.1 Terra (Medium) is on today's frontier: nothing is both smarter and cheaper.
GPT-5.6 Luna (High)GPT-6.1 Terra (Medium)Today's Pareto frontierEvery other model
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