These launched four weeks apart and compete directly at the top of the market. They are built around different ideas about what a phone is for.
Screen and size
The iPhone 18 Pro Max is 6.9 inches at 2868×1320, up to 3000 nits, with Ceramic Shield 2.
The Pixel 11 Pro XL is 6.8 inches, brighter at 3300 nits, with Gorilla Glass Victus 2.
Close enough that neither is a reason to choose.
Camera philosophy
Apple went hardware: a physically variable aperture on the main camera, giving optical control over depth of field, plus 8x optical-quality zoom and the new Reference Image system that cryptographically signs what the sensor captured.
Google went computational, as always. The processing does more of the work, and the results have historically been excellent in difficult light with less user input.
Both take very good photographs. Apple offers more manual control; Google offers better results without thinking about it.
Chip
A20 Pro on 2nm against Tensor G6. Apple wins on raw performance by a clear margin. Google does not compete there and never has – Tensor exists to run machine learning models on the device.
Battery
Apple claims its largest ever increase, around 30 hours of use. The Pixel XL has 5115 mAh and charges slowly.
Advantage to Apple, meaningfully.
Who each suits
Already in one ecosystem: stay there, the switching cost outweighs any difference here.
Starting fresh: Apple for battery, performance and resale value. Google for camera results without effort and a cleaner software experience.