Claude Fable 5.1 vs Claude Fable 5
Claude Fable 5.1 (Anthropic) and Claude Fable 5 (Anthropic) compared on price, context window, speed and independent benchmarks. Claude Fable 5.1 scores higher on the Artificial Analysis Intelligence Index (65.7 vs 62.1), while Claude Fable 5 is 1.0× cheaper on a blended basis. Pick Claude Fable 5.1 for the hardest tasks and Claude Fable 5 when cost dominates.
| Claude Fable 5.1 | Claude Fable 5 | |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Input $/1M | $10.0 | $10.0 |
| Output $/1M | $50.0 | $50.0 |
| Blended $/1M (3:1) | $20.0 | $20.0 |
| Cached input $/1M | $0.25 | $1.00 |
| Context window | 1M | 1M |
| Knowledge cutoff | 2026-06 | 2026-01 |
| License | proprietary | proprietary |
| Speed (tok/s) | 71 | 68 |
| Artificial Analysis Intelligence Index | 65.7 | 62.1 |
| LMArena Elo | — | 1494 |
| GPQA Diamond | 93.7% | 92.6% |
| AIME | — | 99.7%* |
| SWE-bench Verified | — | 95% |
| MMLU-Pro | — | 91.5%* |
| Humanity's Last Exam | 59.1% | 55.5% |