Claude Opus 5.5 (High, Default Fallback) vs GPT-5.6 Luna (Non-reasoning)
Which is better for the money: Claude Opus 5.5 (High, Default Fallback) by Anthropic or GPT-5.6 Luna (Non-reasoning) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Depends on your budget
Claude Opus 5.5 (High, Default Fallback) scores 38.1 points higher (53.6 vs 15.5) but costs 95× as much to run the benchmark ($2172 vs $23.0; flagship vs budget cost classes). They are not alternatives at one budget: pick Claude Opus 5.5 (High, Default Fallback) when you need intelligence above 15.5, and GPT-5.6 Luna (Non-reasoning) when 15.5 is enough.
| Metric | Claude Opus 5.5 (High, Default Fallback) | GPT-5.6 Luna (Non-reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 53.6 | 15.5 | −71.1% GPT-5.6 Luna (Non-rea… is 71.1% less intelligent |
| Total AA cost (lower is better) | $2,172.43 | $22.97 | −98.9% GPT-5.6 Luna (Non-rea… is 98.9% cheaper |
| End-to-end time (lower is better) | 40.99s | 5.06s | −87.7% GPT-5.6 Luna (Non-rea… is 87.7% 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 (Non-reasoning) vs Claude Opus 5.5 (High, Default Fallback): 71.1% less intelligence, 98.9% less cost to run the AA benchmark, and 87.7% faster end-to-end.
Against the frontier
- Claude Opus 5.5 (High, Default Fallback) is on today's frontier: nothing is both smarter and cheaper.
- GPT-5.6 Luna (Non-reasoning) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
Compare something else
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-opus-5-5-high/gpt-5-6-luna-non-reasoning · Markdown: /api/v1/compare/claude-opus-5-5-high/gpt-5-6-luna-non-reasoning?format=md · llms.txt · agent skill