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

Posted by Miguel Enriquez
Miguel Enriquez
2,057 Points

REMs seem redundant. Why not use px instead?

If 1 rem is equal to 16 px, then why not use px instead?

Am I missing some info?

2 Answers

Jennifer Nordell
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STAFF
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Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
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Jennifer Nordell
Treehouse Teacher

Hi there! Close! 1rem is equal to 1x the default font size of the browser Most current browsers have a default size of 16px, but this could change. Also, not all browsers may have the same default font-size. While I don't know the specifics yet, I'm given to understand that Apple will be enabling web browsing on their Apple watch soon. It could be that 16px is too big there, but they have another default size. Instead of divining what the size is, you can just say "the default" by saying 1rem.

Hope this helps! :sparkles:

Pitrov Secondary
Pitrov Secondary
5,121 Points
Pitrov Secondary
Pitrov Secondary
5,121 Points

But he said if a screen is 2x bigger, then 1px is 2x bigger too. So in the Apple Watch 1px is much smaller? I do not know If i understood it correctly

Sean M
Sean M
7,344 Points
Sean M
Sean M
7,344 Points

Because rem makes content proportional to the size of other browsers which is important when using multiple devices.