Grok 4.20 vs GPT Image 1.5
| xAI Grok 4.20 | OpenAI GPT Image 1.5 | |
|---|---|---|
| Vendor | xAI | OpenAI |
| Context window | 2,000,000 | 128,000 |
| Max output | 2,000,000 | — |
| Reasoning | Yes | No |
| Tool calling | Yes | No |
| File input | Yes | Yes |
| Input | text, image | text, image |
| Output | text | image |
| Released | 2026-03-08 | 2025-12-16 |