DALL-E 3 only supports the following sizes: 1024×1024, 1792×1024, or 1024×1792
Stability.AI requires both width and height to be multiples of 64 (e.g., 512, 576, 640, 704, 768)
This requirement is due to the architecture of the model, which uses layered downsampling and upsampling operations that work best with sizes divisible by 64
Optimal image size range: 512–2048 pixels (for both width and height)
Recommended sizes: 512×512, 768×768, 1024×1024, 1024×1536 — depending on your hardware capability
Avoid non-multiples of 64 like 500×600 or 1023×1023, as they may cause errors or degraded performance