Claude 4.5 Haiku (Reasoning) vs Claude Fable 5.1 (Medium, Default Fallback)
Which is better for the money: Claude 4.5 Haiku (Reasoning) by Anthropic or Claude Fable 5.1 (Medium, Default Fallback) by Anthropic? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Depends on your budget
Claude Fable 5.1 (Medium, Default Fallb… scores 32.0 points higher (48.9 vs 16.9) but costs 6.7× as much to run the benchmark ($3983 vs $594; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Fable 5.1 (Medium, Default Fallb… when you need intelligence above 16.9, and Claude 4.5 Haiku (Reasoning) when 16.9 is enough.
| Metric | Claude 4.5 Haiku (Reasoning) | Claude Fable 5.1 (Medium, Default Fallback) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 16.9 | 48.9 | +189.3% Claude Fable 5.1 (Med… is 2.9× more intelligent |
| Total AA cost (lower is better) | $594.08 | $3,983.28 | +570.5% Claude Fable 5.1 (Med… is 6.7× more expensive |
| End-to-end time (lower is better) | 24.38s | 16.07s | −34.1% Claude Fable 5.1 (Med… is 34.1% faster |
| Price per 1M tokens (in / out) | $1.00 / $5.00 | $10.0 / $50.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Fable 5.1 (Medium, Default Fallback) vs Claude 4.5 Haiku (Reasoning): 189.3% more intelligence, 570.5% more cost to run the AA benchmark, and 34.1% faster end-to-end.
Against the frontier
- Claude 4.5 Haiku (Reasoning) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
- 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.
Compare something else
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-4-5-haiku-reasoning/claude-fable-5-1-medium · Markdown: /api/v1/compare/claude-4-5-haiku-reasoning/claude-fable-5-1-medium?format=md · llms.txt · agent skill