GPT-5.5 (Medium) vs GPT-6 Luna (Non-reasoning)
Which is better for the money: GPT-5.5 (Medium) by OpenAI or GPT-6 Luna (Non-reasoning) 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-5.5 (Medium) scores 15.3 points higher (33.8 vs 18.5) but costs 96× as much to run the benchmark ($1833 vs $19.2; premium vs budget cost classes). They are not alternatives at one budget: pick GPT-5.5 (Medium) when you need intelligence above 18.5, and GPT-6 Luna (Non-reasoning) when 18.5 is enough.
| Metric | GPT-5.5 (Medium) | GPT-6 Luna (Non-reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 33.8 | 18.5 | −45.3% GPT-6 Luna (Non-reaso… is 45.3% less intelligent |
| Total AA cost (lower is better) | $1,833.39 | $19.16 | −99.0% GPT-6 Luna (Non-reaso… is 99.0% cheaper |
| End-to-end time (lower is better) | 13.28s | 5.06s | −61.9% GPT-6 Luna (Non-reaso… is 61.9% faster |
| Price per 1M tokens (in / out) | $5.00 / $30.0 | $0.10 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
GPT-6 Luna (Non-reasoning) vs GPT-5.5 (Medium): 45.3% less intelligence, 99.0% less cost to run the AA benchmark, and 61.9% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.5 (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- GPT-6 Luna (Non-reasoning) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
GPT-5.5 (Medium)GPT-6 Luna (Non-reasoning)Today's Pareto frontierEvery other model
Matchup
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