Apple iPhone 16 Pro Max: Screen Size & CSS Viewport

The iPhone 16 Pro Max established a new CSS viewport width of 440×956 — the widest iPhone display up to that point. This extra width compared to the 390px standard iPhone is not trivial: it is 50 additional CSS pixels, roughly equivalent to adding a comfortable side padding to every column in your layout.

At 440px width, single-column mobile layouts can comfortably accommodate slightly wider card designs, two-item grids, and inline icon-text pairings that would feel crowded at 390px. Some developers will over-optimize for 390px and produce layouts that look undersized on the 440px Pro Max — text that is too small, content columns that are too narrow, and excessive whitespace on either side.

The "thinnest bezels on any Apple device" at launch means the display extends to within millimeters of the device edge, reducing the natural thumb resting zone. Tap targets placed at the very edge of the screen — close to the bezel — are less accessible with one-handed use. Review your layout at 440px and ensure that interactive elements have enough inset from the screen edge that they can be tapped without requiring the user to stretch uncomfortably.