Claude Sonnet 5 (Max) vs GPT-5.6 Luna (Medium)
Which is better for the money: Claude Sonnet 5 (Max) 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 Sonnet 5 (Max) scores 13.2 points higher (38.2 vs 25.0) but costs 158× as much to run the benchmark ($6998 vs $44.3; flagship vs budget cost classes). They are not alternatives at one budget: pick Claude Sonnet 5 (Max) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | Claude Sonnet 5 (Max) | GPT-5.6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 38.2 | 25.0 | −34.6% GPT-5.6 Luna (Medium) is 34.6% less intelligent |
| Total AA cost (lower is better) | $6,998.25 | $44.32 | −99.4% GPT-5.6 Luna (Medium) is 99.4% cheaper |
| End-to-end time (lower is better) | 200.39s | 6.19s | −96.9% GPT-5.6 Luna (Medium) is 96.9% faster |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Luna (Medium) vs Claude Sonnet 5 (Max): 34.6% less intelligence, 99.4% less cost to run the AA benchmark, and 96.9% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5 (Max) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Xhigh, Default Fallback) scores 56.00 for $4057.
- 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 Sonnet 5 (Max)GPT-5.6 Luna (Medium)Today's Pareto frontierEvery other model
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