Claude Opus 5.5 (High, Default Fallback) vs GPT-6 Luna (High)
Which is better for the money: Claude Opus 5.5 (High, Default Fallback) by Anthropic or GPT-6 Luna (High) 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
Claude Opus 5.5 (High, Default Fallback) scores 20.7 points higher (53.6 vs 32.9) but costs 45× as much to run the benchmark ($2172 vs $47.9; flagship vs budget cost classes). They are not alternatives at one budget: pick Claude Opus 5.5 (High, Default Fallback) when you need intelligence above 32.9, and GPT-6 Luna (High) when 32.9 is enough.
| Metric | Claude Opus 5.5 (High, Default Fallback) | GPT-6 Luna (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 53.6 | 32.9 | −38.6% GPT-6 Luna (High) is 38.6% less intelligent |
| Total AA cost (lower is better) | $2,172.43 | $47.85 | −97.8% GPT-6 Luna (High) is 97.8% cheaper |
| End-to-end time (lower is better) | 39.33s | 18.94s | −51.8% GPT-6 Luna (High) is 51.8% faster |
| Price per 1M tokens (in / out) | $4.00 / $20.0 | $0.10 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
GPT-6 Luna (High) vs Claude Opus 5.5 (High, Default Fallback): 38.6% less intelligence, 97.8% less cost to run the AA benchmark, and 51.8% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (High, Default Fallback) is on today's frontier: nothing is both smarter and cheaper.
- GPT-6 Luna (High) is on today's frontier: nothing is both smarter and cheaper.
Claude Opus 5.5 (High, Default Fallback)GPT-6 Luna (High)Today's Pareto frontierEvery other model
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