gpt-4.1-nano vs Claude Fable 5.1
| OpenAI gpt-4.1-nano | Anthropic Claude Claude Fable 5.1 | |
|---|---|---|
| Vendor | OpenAI | Anthropic Claude |
| Context window | 1,047,576 | 1,000,000 |
| Max output | 32,768 | 128,000 |
| Reasoning | No | Yes |
| Tool calling | Yes | Yes |
| File input | Yes | Yes |
| Input | text, image | text, image, file |
| Output | text | text |
| Released | 2025-04-14 | 2026-09-01 |