iOS Font Sizes

Below are the font and point sizes used by iOS at the default sizing level. You can read more, including about the accessibility curves, on Appleā€™s documentation.

.largeTitle 34.0 SFUI-Regular
.title1 28.0 SFUI-Regular
.title2 22.0 SFUI-Regular
.title3 20.0 SFUI-Regular
.headline 17.0 SFUI-Semibold
.subheadline 15.0 SFUI-Regular
.body 17.0 SFUI-Regular
.callout 16.0 SFUI-Regular
.footnote 13.0 SFUI-Regular
.caption1 12.0 SFUI-Regular
.caption2 11.0 SFUI-Regular

Usage

Use preferredFont(forTextStyle:) or scaledFont(for:) with the UIFont.TextStyle constants instead of hard-coding font values in your code.

// update when the user changes their settings
label.adjustsFontForContentSizeCategory = true
label.font = UIFont.preferredFont(forTextStyle: .body)

You can use a modified version of the font with the same scaling:

// for a custom font at the normal scaling
let adjustedFont = UIFont(name: "AmericanTypewriter", size: 17.0)

// for the system font, but starting at a different default point size
// this point size value must be defined as a constant, see below
let adjustedFont = UIFont.systemFont(ofSize: 16.0, weight: .regular)

// use the scaled font version so it still updates automatically
label.adjustsFontForContentSizeCategory = true
label.font = UIFontMetrics(forTextStyle: .body).scaledFont(for: adjustedFont)

NOTE: The current point size from preferredFont(forTextStyle:) already includes scaling. Using it as the starting point will produce double-scaled fonts at ridiculous point sizes.