Claude Fable 5.1 (Max, Default Fallback) vs GPT-5.5 (Medium)
Which is better for the money: Claude Fable 5.1 (Max, Default Fallback) by Anthropic or GPT-5.5 (Medium) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-25.
Trade-off
Verdict
Depends on your budget
Claude Fable 5.1 (Max, Default Fallback) scores 19.6 points higher (53.4 vs 33.8) but costs 6.3× as much to run the benchmark ($13129 vs $2095; both flagship class). They are not alternatives at one budget: pick Claude Fable 5.1 (Max, Default Fallback) when you need intelligence above 33.8, and GPT-5.5 (Medium) when 33.8 is enough.
| Metric | Claude Fable 5.1 (Max, Default Fallback) | GPT-5.5 (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 53.4 | 33.8 | −36.7% GPT-5.5 (Medium) is 36.7% less intelligent |
| Total AA cost (lower is better) | $13,128.86 | $2,095.12 | −84.0% GPT-5.5 (Medium) is 84.0% cheaper |
| End-to-end time (lower is better) | 224.39s | 12.63s | −94.4% GPT-5.5 (Medium) is 94.4% faster |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $5.00 / $30.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.5 (Medium) vs Claude Fable 5.1 (Max, Default Fallback): 36.7% less intelligence, 84.0% less cost to run the AA benchmark, and 94.4% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Fable 5.1 (Max, Default Fallback) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Max, Default Fallback) scores 57.60 for $8708.
- GPT-5.5 (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
Claude Fable 5.1 (Max, Default Fallback)GPT-5.5 (Medium)Today's Pareto frontierEvery other model
Matchup
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