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CSS CSS Basics (2014) Understanding Values and Units Rem Units

Posted by Njdeh Satourian
Njdeh Satourian
1,413 Points

It describes a rem unit as relative only to the root element on the page. Does this mean it is always relative to 16px?

Was just a little confused on this one part. Would appreciate any insight!

Sika Stanton
Sika Stanton
2,198 Points

16 px is the default but you can change the root font-size like this:

html { font-size: 62.5%; }

1 Answer

tobart
tobart
13,518 Points
tobart
tobart
13,518 Points

Hi Nideh, it depends on the base-font-size every browser has. 16px is a common one for nearly every browser. Just check Google Chrome Preferences for example. Further more it is defined as root em, which in this case always sticks to the defined root element, so to speak the html-element or tag.