In many icon systems (YouTube, Spotify, Apple Music), play icons are not mathematically centered inside circles. They are optically centered.
Today most designers fix this manually by nudging shapes until they “look centered”.
I'm collecting perceptual data to better understand how people visually perceive centering. The goal is to explore whether an "optical center" model could be defined.
Long term I would like to build:
• a CSS optical-center property for developers
• a Figma plugin that can automatically place icons where they *look* centered
The experiment takes about 5 minutes (40 steps) and works on both mobile and desktop.
No login required.
👉 https://harley-sponsored-toolbox-operation.trycloudflare.com/
After data collection I plan to share the dataset publicly.
I'm also curious how designers here currently handle optical centering in icon systems.