Optical size

Optical size refers to how a font appears in terms of its visual weight and spacing at different sizes. It accounts for subtle design adjustments that make the text more readable and visually balanced, such as slight changes in character width, stroke thickness, or spacing when the font is scaled up or down. These adjustments help ensure that the font maintains its intended style and clarity across various sizes, providing an optimized reading experience. In essence, optical size is a design feature that fine-tunes a font’s appearance depending on how large or small it is displayed.