iPhone screen sizes

Points, pixels and scale

Pixels are the dots on the panel. Points are the unit your code uses: a 44 point button is about the same physical size on every iPhone. The scale factor is how many pixels make one point along each edge, so the iPhone 17 Pro's 402 × 874 points at @3x become 1206 × 2622 pixels.

Web pages follow the same rule. With width=device-width in the viewport tag, Safari on iPhone gives the page a width in CSS pixels equal to the screen width in points, which is why iPhone widths in CSS run from 320 to 440.

The iPhone 6s Plus, 7 Plus and 8 Plus are the exception to points times scale. They draw at 1242 × 2208 pixels, which is 414 × 736 points at @3x, and then scale the image down to their 1080 × 1920 panel. That is also why App Store Connect asks for 1242 × 2208 screenshots for them.

Why a 6.9-inch iPhone measures 6.86 inches

Apple names screen sizes rounded, and the real screen has rounded corners, so its tech specs pages add a footnote with the measured diagonal:

"The iPhone 17 Pro Max display has rounded corners that follow a beautiful curved design, and these corners are within a standard rectangle. When measured as a standard rectangular shape, the screen is 6.86 inches diagonally (actual viewable area is less)."

The table shows that measured figure under the size wherever Apple gives one. For layout it changes nothing, since your code works in points either way.

A size that is not in the table yet

App Store Connect already lists screenshot sizes for an iPhone Duo with two displays, 1398 × 2034 pixels outside and 2007 × 2853 pixels inside, and says: "Starting in April 2027, screenshots will be required for any app using the iOS 27.1 SDK or later." Apple has not released it yet, so it gets a row here once its tech specs page exists. What that means for your listing is in the App Store screenshot sizes guide.