Claude Sonnet 5.5 (Medium, Default Fallback) vs GPT-5.6 Luna (Max)
Which is better for the money: Claude Sonnet 5.5 (Medium, Default Fallback) by Anthropic or GPT-5.6 Luna (Max) 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 5.5 (Medium, Default Fall… scores 3.5 points higher (40.8 vs 37.3) but costs 1.9× as much to run the benchmark ($622 vs $320; premium vs mid-range cost classes). Pick Claude Sonnet 5.5 (Medium, Default Fall… when the extra intelligence is worth the premium, otherwise GPT-5.6 Luna (Max).
| Metric | Claude Sonnet 5.5 (Medium, Default Fallback) | GPT-5.6 Luna (Max) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 40.8 | 37.3 | −8.6% GPT-5.6 Luna (Max) is 8.6% less intelligent |
| Total AA cost (lower is better) | $622.28 | $319.93 | −48.6% GPT-5.6 Luna (Max) is 48.6% cheaper |
| End-to-end time (lower is better) | 7.86s | 124.29s | +1481.3% GPT-5.6 Luna (Max) is 1481.3% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Luna (Max) vs Claude Sonnet 5.5 (Medium, Default Fallback): 8.6% less intelligence, 48.6% less cost to run the AA benchmark, and 1481.3% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5.5 (Medium, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
- GPT-5.6 Luna (Max) is off the frontier: at the same or lower cost, MiMo-V2.6-Pro scores 46.30 for $207.
Claude Sonnet 5.5 (Medium, Default Fallback)GPT-5.6 Luna (Max)Today's Pareto frontierEvery other model
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