Claude Fable 5.1 (Low, Default Fallback) vs GPT-5.6 Terra (Xhigh)
Which is better for the money: Claude Fable 5.1 (Low, Default Fallback) by Anthropic or GPT-5.6 Terra (Xhigh) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Trade-off
Verdict
Depends on your budget
Claude Fable 5.1 (Low, Default Fallback) scores 8.8 points higher (46.8 vs 38.0) but costs 2.7× as much to run the benchmark ($3158 vs $1187; flagship vs premium cost classes). Pick Claude Fable 5.1 (Low, Default Fallback) when the extra intelligence is worth the premium, otherwise GPT-5.6 Terra (Xhigh).
| Metric | Claude Fable 5.1 (Low, Default Fallback) | GPT-5.6 Terra (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 46.8 | 38.0 | −18.8% GPT-5.6 Terra (Xhigh) is 18.8% less intelligent |
| Total AA cost (lower is better) | $3,157.66 | $1,186.77 | −62.4% GPT-5.6 Terra (Xhigh) is 62.4% cheaper |
| End-to-end time (lower is better) | 10.89s | 33.63s | +208.8% GPT-5.6 Terra (Xhigh) is 208.8% slower |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Terra (Xhigh) vs Claude Fable 5.1 (Low, Default Fallback): 18.8% less intelligence, 62.4% less cost to run the AA benchmark, and 208.8% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Fable 5.1 (Low, Default Fallback) is off the frontier: at the same or lower cost, Kimi K3.1 Pro scores 55.10 for $3117.
- GPT-5.6 Terra (Xhigh) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
Claude Fable 5.1 (Low, Default Fallback)GPT-5.6 Terra (Xhigh)Today's Pareto frontierEvery other model
Matchup
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