Claude Fable 5.1 vs Muse Spark 1.3
Claude Fable 5.1 vs Muse Spark 1.3: which AI model is cheaper, has the larger context window and more capabilities? Side-by-side comparison updated daily.
Quick verdict
- Muse Spark 1.3 is 10× cheaper than Claude Fable 5.1 for the same mix of input and output tokens.
- Muse Spark 1.3 has the larger context window (1M), useful for long documents and big codebases.
- Muse Spark 1.3 is the more recent release (Sep 2, 2026).
- Claude Fable 5.1 scores higher on independent tests (overall index 165.0 vs 156.9).
- Choose Muse Spark 1.3 if cost matters most; choose Claude Fable 5.1 if you need its specific strengths above. For the best results, test both on your own prompts.
| Claude Fable 5.1 | Muse Spark 1.3 | |
|---|---|---|
| Company | Anthropic | Meta |
| Released | Sep 1, 2026 | Sep 2, 2026 ● |
| Overall index | 165.0 ● | 156.9 |
| AIME math | 100% ● | 99.2% |
| FrontierMath | 90.2% ● | 74.4% |
| SimpleQA Verified | 70.8% | — |
| Input (per 1M tokens) | $10 | $1.25 ● |
| Output (per 1M tokens) | $50 | $4.25 ● |
| Cost for 1M input + 1M output tokens | $60.00 | $5.50 ● |
| Providers | 4 ● | 1 |
| Context | 1M | 1M ● |
| Max output | 128K | 944K ● |
| Inputs | Text, Image, Files | Text, Image, Video, Files ● |
| Outputs | Text | Text |
| Reasoning | ✓ | ✓ |
| Tool use | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Open weights | — | — |