Claude Sonnet 5.5 (Max, Default Fallback) vs GPT-5.6 Luna (High)

Which is better for the money: Claude Sonnet 5.5 (Max, Default Fallback) 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

AnthropicClaude Sonnet 5.5 (Max, Default Fallback)Off the frontier

Intelligence: 56.00
Total cost: $7260

OpenAIGPT-5.6 Luna (High)Off the frontier

Intelligence: 32.10
Total cost: $108

Verdict

Depends on your budget

Claude Sonnet 5.5 (Max, Default Fallbac… scores 23.9 points higher (56.0 vs 32.1) but costs 67× as much to run the benchmark ($7260 vs $108; flagship vs mid-range cost classes). They are not alternatives at one budget: pick Claude Sonnet 5.5 (Max, Default Fallbac… when you need intelligence above 32.1, and GPT-5.6 Luna (High) when 32.1 is enough.

Metric	Claude Sonnet 5.5 (Max, Default Fallback)	GPT-5.6 Luna (High)	Difference
Intelligence (higher is better)	56.0	32.1	−42.7% GPT-5.6 Luna (High) is 42.7% less intelligent
Total AA cost (lower is better)	$7,259.50	$108.15	−98.5% GPT-5.6 Luna (High) is 98.5% cheaper
End-to-end time (lower is better)	447.79s	14.62s	−96.7% GPT-5.6 Luna (High) is 96.7% 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 5.5 (Max, Default Fallback): 42.7% less intelligence, 98.5% less cost to run the AA benchmark, and 96.7% faster end-to-end.

Open this matchup in the interactive picker Claude Sonnet 5.5 (Max, Default Fallback): what beats it GPT-5.6 Luna (High): what beats it

Today's Pareto frontier

Against the frontier

Claude Sonnet 5.5 (Max, Default Fallback) 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 (High) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (High) scores 37.80 for $94.1.

Claude Sonnet 5.5 (Max, Default Fallback)GPT-5.6 Luna (High)Today's Pareto frontierEvery other model

Matchup

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Agents: Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-sonnet-5-5/gpt-5-6-luna-high · Markdown: /api/v1/compare/claude-sonnet-5-5/gpt-5-6-luna-high?format=md · llms.txt · agent skill