Icon Fonts: Mind the Baseline

Earlier this week, I made my first custom icon font using IcoMoon (implemented with Filament Group’s “bulletproof” technique).

I set my grid sizes and exported, but all the icons felt a little higher than I wanted them to be in relation to their surrounding elements. I did some finagling in CSS, but found the results varied (sometimes wildly) between platforms.

After some fruitless Googling, I trudged through the font’s preferences and found the culprit: A rather diminutive baseline height value. In IcoMoon, this is under Preferences, then Font Metrics.

Here’s a quick example at the default height (6.25%):

Here are the same elements and icons, but with a larger baseline height (18.75%):

Lesson learned: If the icon font’s vertical alignment is off, adjust its baseline height before resorting to CSS tweaks.

The more you know…