Claude Fable 5 vs Grok 4.1 Fast
Head to head on 23 shared benchmarks, with price, context window, and release dates.
Benchmark scores
49evals · sort by any column, ⤢ to expand fullscreen
| Model | ||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Claude Fable 5 Anthropic | 71.8% | 1933elo | 83 | 92.6% | 55.5% | 63.5% | 81.4% | 78.6% | 80.0% | 59.9% | 88.5% | 93.9% | 87.3% | 56.1% | 88.5% | 68.9% | 95.0% | 51.9% | 60.2% | 76.9% | 62.9% | 90.4% | 98.5% | - | - | 17.4% | 83.9% | 38.6% | 90.0% | 1340elo | 78.0% | 56.3% | 29.3% | 29.8% | 1932elo | - | 66.0% | - | - | 13.3% | - | - | - | - | 85.0% | 80.3% | 88.0% | 66.0% | 74.2% | 69.4% |
| Grok 4.1 Fast xAI | 66.0% | 1324elo | 40.1 | 63.7% | 5.1% | 36.5% | 64.7% | 69.6% | 52.2% | 28.2% | 74.3% | 83.7% | 80.2% | 28.1% | 78.7% | 42.6% | 4.0% | 31.3% | 29.6% | 73.1% | 14.4% | 1.2% | 63.7% | 62.0% | 34.3% | - | - | - | - | - | - | - | - | - | - | 11.8 | - | 35.0% | 80.2% | - | 39.9% | 60.8% | 100.0% | 74.3% | - | - | - | - | - | 51.0% |
2 / 2 models
| Attribute | Claude Fable 5 Anthropic | Grok 4.1 Fast xAI |
|---|---|---|
| Description | Claude Fable 5 is Anthropic's most capable widely released model, built for the most demanding reasoning and long-horizon agentic work. Shares its base model with the invitation-only Claude Mythos 5. | Grok 4.1 Fast is an AI model from xAI. |
| Family | Claude | Grok |
| Params | - | - |
| Open weights | closed | closed |
| License | - | proprietary |
| Released | 9 Jun 2026 | 19 Nov 2025 |
| Context | 1,000,000 | - |
| Input $/1M | $10.00 | - |
| Output $/1M | $50.00 | - |
| Cache read $/1M | $1.000 | - |
| Cache write $/1M | $12.500 | - |
| Speed | 66 tok/s | 0 tok/s |
| Latency | 49.62 s | 0.00 s |
| Modalities | text, image, file | text |
| Providers | - | - |
| Publisher | Anthropic | xAI |
| Reported scores | Finance Agent (v2)56.3% IFBench63.5% (AA) Swebenchpro80.3% LiveBench - Math93.9% (LiveBench) LiveBench - Coding78.6% (LiveBench) | Infraresolutionbench80.2% (150 samples) Agent Diff Bench62.0% (179 samples) Medpt100.0% (15 samples) Hanabi11.8 (15 samples) SciCode29.6% (AA) |
FAQ
- Is Claude Fable 5 or Grok 4.1 Fast better?
- Across the 23 benchmarks both models report on Sophon, Claude Fable 5 leads on 23 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do Claude Fable 5 and Grok 4.1 Fast compare on GPQA Diamond?
- Claude Fable 5 scores 92.6% and Grok 4.1 Fast scores 63.7% on GPQA Diamond.
- When were Claude Fable 5 and Grok 4.1 Fast released?
- Claude Fable 5 was released 9 Jun 2026 by Anthropic. Grok 4.1 Fast was released 19 Nov 2025 by xAI.
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