When you’re creating a new file in Affinity Designer, Affinity Photo, or Photoshop, it will prompt you for DPI (dots per inch), which can be confusing when you’re making something for screen use like a macOS app icon or iOS app icon.
Here’s how to think about it:
TL;DR for macOS app icons:
Set DPI to 72 or 144, but it doesn’t really matter — what matters is the pixel dimensions (e.g., 1024×1024 px). DPI only matters for printing, not screen.
Why does DPI show up?
DPI is used to describe how densely pixels are packed in an inch of printed material. For example:
- 72 DPI = 72 pixels per inch (historical standard for screens)
- 300 DPI = high-quality print resolution
But for digital use, DPI is just metadata — the operating system and Xcode care about the pixel dimensions, not the DPI.
Best settings when creating your icon file:
- Width & Height: 1024×1024 pixels
- Resolution / DPI: 72 (or 144, doesn’t matter for screens)
- Color mode: RGB (not CMYK)
- Background: Transparent (if your icon needs it)
Lastly, you can download the template that Apple provides here.
