Claude Fable 5 (Max, Opus 4.8 Fallback) vs GPT-5.6 Terra (Medium)
Which is better for the money: Claude Fable 5 (Max, Opus 4.8 Fallback) by Anthropic or GPT-5.6 Terra (Medium) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Depends on your budget
Claude Fable 5 (Max, Opus 4.8 Fallback) scores 19.5 points higher (49.6 vs 30.1) but costs 25× as much to run the benchmark ($11161 vs $447; flagship vs mid-range cost classes). They are not alternatives at one budget: pick Claude Fable 5 (Max, Opus 4.8 Fallback) when you need intelligence above 30.1, and GPT-5.6 Terra (Medium) when 30.1 is enough.
| Metric | Claude Fable 5 (Max, Opus 4.8 Fallback) | GPT-5.6 Terra (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 49.6 | 30.1 | −39.3% GPT-5.6 Terra (Medium) is 39.3% less intelligent |
| Total AA cost (lower is better) | $11,160.86 | $446.53 | −96.0% GPT-5.6 Terra (Medium) is 96.0% cheaper |
| End-to-end time (lower is better) | 85.47s | 6.06s | −92.9% GPT-5.6 Terra (Medium) is 92.9% faster |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Terra (Medium) vs Claude Fable 5 (Max, Opus 4.8 Fallback): 39.3% less intelligence, 96.0% less cost to run the AA benchmark, and 92.9% faster end-to-end.
Against the frontier
- Claude Fable 5 (Max, Opus 4.8 Fallback) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Max, Default Fallback) scores 57.60 for $8708.
- GPT-5.6 Terra (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Medium) scores 47.80 for $361.
Compare something else
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-fable-5/gpt-5-6-terra-medium · Markdown: /api/v1/compare/claude-fable-5/gpt-5-6-terra-medium?format=md · llms.txt · agent skill