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Alice Stiles
3,898 PointsI don't understand the purpose of the px to em function
Surely if you want something to be a fixed size, you can use px, and if you want it to depend on font size you can use em? Why have a function to take a px value and convert to em? Am I missing something?
1 Answer
Brian Jensen
Treehouse StaffHiya Alice Stiles!
You're not missing something, it's a great question!
One core reason is accessibility. Users can adjust their browser's default font size for readability. Elements sized with em units will scale accordingly, respecting the user's preference. In contrast, px units are fixed and won't adjust, potentially leading to readability issues. Also, using em units allows your layout to adapt when the context changes. For example, if a parent element's font size changes due to a media query, all child elements using em units will scale proportionally, maintaining consistent visual proportions across different screen sizes.
Lastly, designers often provide specifications in pixels. Converting these to em units bridges the gap between design precision and responsive implementation. The function automates this conversion, reducing manual calculation errors.