Claude Fable 5 vs GPT-5.5 Pro
Claude Fable 5 vs GPT-5.5 Pro: which AI model is cheaper, has the larger context window and more capabilities? Side-by-side comparison updated daily.
Quick verdict
- Claude Fable 5 is 3.4× cheaper than GPT-5.5 Pro for the same mix of input and output tokens.
- GPT-5.5 Pro has the larger context window (1.1M), useful for long documents and big codebases.
- Claude Fable 5 is the more recent release (Jun 9, 2026).
- Claude Fable 5 scores higher on independent tests (overall index 163.6 vs 162.5).
- Claude Fable 5 is both cheaper and better rated: for most uses it is the better choice.
| Claude Fable 5 | GPT-5.5 Pro | |
|---|---|---|
| Company | Anthropic | OpenAI |
| Released | Jun 9, 2026 ● | Apr 24, 2026 |
| Overall index | 163.6 ● | 162.5 |
| GPQA Diamond | 85.9% | — |
| AIME math | 100% | — |
| FrontierMath | 87.0% | 87.7% ● |
| SimpleQA Verified | 70.7% | — |
| Input (per 1M tokens) | $10 ● | $30 |
| Output (per 1M tokens) | $50 ● | $180 |
| Cost for 1M input + 1M output tokens | $60.00 ● | $210 |
| Providers | 6 ● | 2 |
| Context | 1M | 1.1M ● |
| Max output | 128K | 128K |
| Inputs | Text, Image, Files | Files, Image, Text |
| Outputs | Text | Text |
| Reasoning | ✓ | ✓ |
| Tool use | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Open weights | — | — |