Effort levels by model › Claude Fable 5.1
Claude Fable 5.1 reasoning effort levels: intelligence, cost and speed
How much smarter Claude Fable 5.1 gets at each reasoning effort, what each level costs per task, and how fast it answers. Benchmarks from Artificial Analysis.
| Effort | Intelligence Index | Gain vs. previous | Cost per task | Output tokens/s |
|---|---|---|---|---|
| low Best intelligence per dollar | 38 | — | $4.47 | 57 |
| medium | 43 | +5 | $5.56 | 58 |
| high | 47 | +4 | $7.54 | 58 |
| xhigh | 50 | +3 | $10.85 | 63 |
| max | 49 | -1 | $12.99 | 71 |
API: $10 / $50 per 1M input / output tokens.
Source: Artificial Analysis LLM Leaderboard, checked 2026-11-02.