Claude Fable 5.1 (Medium, Default Fallback) vs Claude Opus 5 (Medium)
Which is better for the money: Claude Fable 5.1 (Medium, Default Fallback) by Anthropic or Claude Opus 5 (Medium) by Anthropic? 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 (Medium, Default Fallb… scores 4.1 points higher (48.9 vs 44.8) but costs 1.5× as much to run the benchmark ($3983 vs $2732; both flagship class). Pick Claude Fable 5.1 (Medium, Default Fallb… when the extra intelligence is worth the premium, otherwise Claude Opus 5 (Medium).
| Metric | Claude Fable 5.1 (Medium, Default Fallback) | Claude Opus 5 (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 48.9 | 44.8 | −8.4% Claude Opus 5 (Medium) is 8.4% less intelligent |
| Total AA cost (lower is better) | $3,983.28 | $2,731.91 | −31.4% Claude Opus 5 (Medium) is 31.4% cheaper |
| End-to-end time (lower is better) | 16.18s | 12.85s | −20.6% Claude Opus 5 (Medium) is 20.6% faster |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $5.00 / $25.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Opus 5 (Medium) vs Claude Fable 5.1 (Medium, Default Fallback): 8.4% less intelligence, 31.4% less cost to run the AA benchmark, and 20.6% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Fable 5.1 (Medium, Default Fallback) is off the frontier: at the same or lower cost, Kimi K3.1 Pro scores 55.10 for $3117.
- Claude Opus 5 (Medium) is off the frontier: at the same or lower cost, Claude Opus 5.5 (High, Default Fallback) scores 53.60 for $2172.
Claude Fable 5.1 (Medium, Default Fallback)Claude Opus 5 (Medium)Today's Pareto frontierEvery other model
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