Claude 4.5 Sonnet (Reasoning) vs Claude Fable 5 (Max, Opus 4.8 Fallback)
Which is better for the money: Claude 4.5 Sonnet (Reasoning) by Anthropic or Claude Fable 5 (Max, Opus 4.8 Fallback) by Anthropic? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-25.
Depends on your budget
Claude Fable 5 (Max, Opus 4.8 Fallback) scores 28.9 points higher (49.6 vs 20.7) but costs 7.4× as much to run the benchmark ($11161 vs $1501; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Fable 5 (Max, Opus 4.8 Fallback) when you need intelligence above 20.7, and Claude 4.5 Sonnet (Reasoning) when 20.7 is enough.
| Metric | Claude 4.5 Sonnet (Reasoning) | Claude Fable 5 (Max, Opus 4.8 Fallback) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 20.7 | 49.6 | +139.6% Claude Fable 5 (Max, … is 2.4× more intelligent |
| Total AA cost (lower is better) | $1,501.22 | $11,160.86 | +643.5% Claude Fable 5 (Max, … is 7.4× more expensive |
| End-to-end time (lower is better) | 21.53s | 85.37s | +296.5% Claude Fable 5 (Max, … is 296.5% slower |
| Price per 1M tokens (in / out) | $3.00 / $15.0 | $10.0 / $50.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Fable 5 (Max, Opus 4.8 Fallback) vs Claude 4.5 Sonnet (Reasoning): 139.6% more intelligence, 643.5% more cost to run the AA benchmark, and 296.5% slower end-to-end.
Against the frontier
- Claude 4.5 Sonnet (Reasoning) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- 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.
Compare something else
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-4-5-sonnet-thinking/claude-fable-5 · Markdown: /api/v1/compare/claude-4-5-sonnet-thinking/claude-fable-5?format=md · llms.txt · agent skill