Claude Opus 5.5 (Max, Default Fallback) vs GPT-5.6 Luna (Medium)
Which is better for the money: Claude Opus 5.5 (Max, Default Fallback) by Anthropic or GPT-5.6 Luna (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
Claude Opus 5.5 (Max, Default Fallback) scores 32.6 points higher (57.6 vs 25.0) but costs 196× as much to run the benchmark ($8708 vs $44.3; flagship vs budget cost classes). They are not alternatives at one budget: pick Claude Opus 5.5 (Max, Default Fallback) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | Claude Opus 5.5 (Max, Default Fallback) | GPT-5.6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 57.6 | 25.0 | −56.6% GPT-5.6 Luna (Medium) is 56.6% less intelligent |
| Total AA cost (lower is better) | $8,708.20 | $44.32 | −99.5% GPT-5.6 Luna (Medium) is 99.5% cheaper |
| End-to-end time (lower is better) | 711.14s | 6.50s | −99.1% GPT-5.6 Luna (Medium) is 99.1% faster |
| Price per 1M tokens (in / out) | $4.00 / $20.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Luna (Medium) vs Claude Opus 5.5 (Max, Default Fallback): 56.6% less intelligence, 99.5% less cost to run the AA benchmark, and 99.1% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (Max, Default Fallback) is on today's frontier: nothing is both smarter and cheaper.
- 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.
Claude Opus 5.5 (Max, Default Fallback)GPT-5.6 Luna (Medium)Today's Pareto frontierEvery other model
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