Claude Opus 5 (Low) vs GPT-5.6 Luna (Medium)
Which is better for the money: Claude Opus 5 (Low) 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 (Low) scores 14.4 points higher (39.4 vs 25.0) but costs 35× as much to run the benchmark ($1561 vs $44.3; premium vs budget cost classes). They are not alternatives at one budget: pick Claude Opus 5 (Low) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | Claude Opus 5 (Low) | GPT-5.6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 39.4 | 25.0 | −36.5% GPT-5.6 Luna (Medium) is 36.5% less intelligent |
| Total AA cost (lower is better) | $1,560.91 | $44.32 | −97.2% GPT-5.6 Luna (Medium) is 97.2% cheaper |
| End-to-end time (lower is better) | 11.37s | 6.43s | −43.4% GPT-5.6 Luna (Medium) is 43.4% faster |
| Price per 1M tokens (in / out) | $5.00 / $25.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Luna (Medium) vs Claude Opus 5 (Low): 36.5% less intelligence, 97.2% less cost to run the AA benchmark, and 43.4% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5 (Low) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- 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 (Low)GPT-5.6 Luna (Medium)Today's Pareto frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-opus-5-low/gpt-5-6-luna-medium · Markdown: /api/v1/compare/claude-opus-5-low/gpt-5-6-luna-medium?format=md · llms.txt · agent skill