Claude Fable 5.1 vs GLM 5.3 Prime
Claude Fable 5.1 vs GLM 5.3 Prime: which AI model is cheaper, has the larger context window and more capabilities? Side-by-side comparison updated daily.
Quick verdict
- GLM 5.3 Prime is 4.7× cheaper than Claude Fable 5.1 for the same mix of input and output tokens.
- Both have the same context window.
- GLM 5.3 Prime is the more recent release (Sep 23, 2026).
- Only Claude Fable 5.1 accepts images as input.
- Choose GLM 5.3 Prime 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 | GLM 5.3 Prime | |
|---|---|---|
| Company | Anthropic | Z.ai (Zhipu) |
| Released | Sep 1, 2026 | Sep 23, 2026 ● |
| Overall index | 165.0 | — |
| AIME math | 100% | — |
| FrontierMath | 90.2% | — |
| SimpleQA Verified | 70.8% | — |
| Input (per 1M tokens) | $10 | $2.80 ● |
| Output (per 1M tokens) | $50 | $8.80 ● |
| Cost for 1M input + 1M output tokens | $60.00 | $11.60 ● |
| Providers | 4 ● | 1 |
| Context | 1M | 1M |
| Max output | 128K | 128K ● |
| Inputs | Text, Image, Files ● | Text |
| Outputs | Text | Text |
| Reasoning | ✓ | ✓ |
| Tool use | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Open weights | — | — |