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106 points
Submitted by
Aazib Chaudhry
about 3 years ago

What are ems?

Okay so, I am not really sure of what the em unit is. The lesson states: "The font-size unit em is a relative measure: one em is equal to the default font size on whatever screen the user is using."
What is meant by the default font size of the screen?

2 votes


Em's are just something written into each computer/phone. When it sees an em, it sees a certain size in which to put text. This is because, if I wrote a program on my massive screen, and then you tried to use it on your tiny iphone, it may be too big for your iphone screen, so em's "standardize" in a sense. It is like me saying to you that my desk is two arms wide. Your measurement would be different because you may have longer arms than mine. I hope that helps.

334 points
Submitted by
almost 3 years ago

1 Comment

7081d4b9ac8d1a42d6ce09ea751a23ff?s=140&d=retro Aazib Chaudhry almost 3 years ago

That was a clear explanation. Thanks.

1 vote


the default font-size is 16px; so 1em = 16px.
so 1.5 em is 24px; 0.5em is 8px.

in combination with percentage they are very useful for mobile browsers. but i can't get my head around the idea.

so if you change the font-size to 20px, 2em would be 40px;

2410 points
Submitted by
about 3 years ago


7081d4b9ac8d1a42d6ce09ea751a23ff?s=140&d=retro Aazib Chaudhry about 3 years ago

Does that mean that the size of the majority of text on my computer is 16px?

593d545c83696644420003b7_64554016 stetim94 about 3 years ago

computer? no. webpages? yes, if the website hasn't changed it. which i think most websites have done.

7081d4b9ac8d1a42d6ce09ea751a23ff?s=140&d=retro Aazib Chaudhry about 3 years ago

Okay, got it. Thanks for helping me out.