Claude Sonnet 5.5 (High, Default Fallback) vs GPT-6 Luna (Medium)
Which is better for the money: Claude Sonnet 5.5 (High, Default Fallback) by Anthropic or GPT-6 Luna (Medium) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-24.
Trade-off
Verdict
Depends on your budget
Claude Sonnet 5.5 (High, Default Fallba… scores 16.9 points higher (46.8 vs 29.9) but costs 33× as much to run the benchmark ($1027 vs $31.2; premium vs budget cost classes). They are not alternatives at one budget: pick Claude Sonnet 5.5 (High, Default Fallba… when you need intelligence above 29.9, and GPT-6 Luna (Medium) when 29.9 is enough.
| Metric | Claude Sonnet 5.5 (High, Default Fallback) | GPT-6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 46.8 | 29.9 | −36.1% GPT-6 Luna (Medium) is 36.1% less intelligent |
| Total AA cost (lower is better) | $1,027.40 | $31.17 | −97.0% GPT-6 Luna (Medium) is 97.0% cheaper |
| End-to-end time (lower is better) | 14.89s | 8.25s | −44.6% GPT-6 Luna (Medium) is 44.6% faster |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $0.10 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
GPT-6 Luna (Medium) vs Claude Sonnet 5.5 (High, Default Fallback): 36.1% less intelligence, 97.0% less cost to run the AA benchmark, and 44.6% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5.5 (High, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- GPT-6 Luna (Medium) is on today's frontier: nothing is both smarter and cheaper.
Claude Sonnet 5.5 (High, Default Fallback)GPT-6 Luna (Medium)Today's Pareto frontierEvery other model
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