Claude Fable 5.1 (Medium, Default Fallback) vs Grok 4.5 (High)
Which is better for the money: Claude Fable 5.1 (Medium, Default Fallback) by Anthropic or Grok 4.5 (High) by SpaceXAI? 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 10.1 points higher (48.9 vs 38.8) but costs 3.2× as much to run the benchmark ($3983 vs $1244; 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 38.8, and Grok 4.5 (High) when 38.8 is enough.
| Metric | Claude Fable 5.1 (Medium, Default Fallback) | Grok 4.5 (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 48.9 | 38.8 | −20.7% Grok 4.5 (High) is 20.7% less intelligent |
| Total AA cost (lower is better) | $3,983.28 | $1,243.85 | −68.8% Grok 4.5 (High) is 68.8% cheaper |
| End-to-end time (lower is better) | 14.35s | 19.45s | +35.5% Grok 4.5 (High) is 35.5% slower |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $2.00 / $6.00 | |
| Input modalities | Text, Image | Text, Image |
Grok 4.5 (High) vs Claude Fable 5.1 (Medium, Default Fallback): 20.7% less intelligence, 68.8% less cost to run the AA benchmark, and 35.5% slower 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.
- Grok 4.5 (High) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
Claude Fable 5.1 (Medium, Default Fallback)Grok 4.5 (High)Today's Pareto frontierEvery other model
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