What is the definitive iPhone X corner radius?

I’ve been experimenting and have found no conclusive corner radius for the iPhone X.

  • Some sources, such as iPhone X Screen Demystified – PaintCode, say its 40pts.
  • Some say it’s 44, like UI Design for iPhone X: Top Elements and the Notch – Max Rudberg.

Using Xcode, I created a circle with a width and length of 80 (so radius 40), and put it in the top left corner of the iPhone X (so x and y are zero), there is a tiny white gap between the circle and the the edge of the screen, which you can see here:

I also tried another method, doing this with a button:

button.frame.size.height = 812
button.frame.size.width = 375
button.layer.cornerRadius = 40
button.center = self.view.center

With this I am left with:

So the question is, what is the real corner radius? Or what is going on with Xcode?

All topic