Claude Sonnet 5 (Xhigh) vs GPT-5.6 Luna (High)
Which is better for the money: Claude Sonnet 5 (Xhigh) by Anthropic or GPT-5.6 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 Sonnet 5 (Xhigh) scores 2.3 points higher (34.4 vs 32.1) but costs 30× as much to run the benchmark ($3255 vs $108; flagship vs mid-range cost classes). They are not alternatives at one budget: pick Claude Sonnet 5 (Xhigh) when you need intelligence above 32.1, and GPT-5.6 Luna (High) when 32.1 is enough.
| Metric | Claude Sonnet 5 (Xhigh) | GPT-5.6 Luna (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 34.4 | 32.1 | −6.7% GPT-5.6 Luna (High) is 6.7% less intelligent |
| Total AA cost (lower is better) | $3,255.40 | $108.15 | −96.7% GPT-5.6 Luna (High) is 96.7% cheaper |
| End-to-end time (lower is better) | 32.78s | 16.71s | −49.0% GPT-5.6 Luna (High) is 49.0% 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 (High) vs Claude Sonnet 5 (Xhigh): 6.7% less intelligence, 96.7% less cost to run the AA benchmark, and 49.0% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5 (Xhigh) is off the frontier: at the same or lower cost, Kimi K3.1 Pro scores 55.10 for $3117.
- GPT-5.6 Luna (High) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (High) scores 37.80 for $94.1.
Claude Sonnet 5 (Xhigh)GPT-5.6 Luna (High)Today's Pareto frontierEvery other model
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-sonnet-5-xhigh/gpt-5-6-luna-high · Markdown: /api/v1/compare/claude-sonnet-5-xhigh/gpt-5-6-luna-high?format=md · llms.txt · agent skill