There are several different ways you can declare the size of a font in CSS. The units fall into one of two categories - absolute and relative.
Absolute units are fixed. Once they are declared, their size cannot be altered by changing the font size of some other element. Those include px, pt and pc units.
The size of relative units is determined by the size of a parent element. Their size can be altered by changing the sizing of that dependent element. Those include %, em, rem, vw, vh, vmin, vmax, etc.
What units do you normally prefer to use?
Top comments (43)
Awesome to hear that 👍💯✨
call me old fashioned but 90% of my font-sizes are
16pxIn visual display media, always
rem, except on the root of the document (where I usually use pixels because they are de-facto consistent across all platforms. Usingrems means that the site layout works correctly no matter how much zoom the user uses, because it all scales together.For print media it gets a bit trickier. I would normally use points there because most printers will know how to handle that correctly without multiple unit conversions (unlike other absolute units which may or may not need to be converted twice). I might use
ems if I need to offset size relative to the parent font size for some reason, but would probably not use relative units for anything else, instead relying on the (sane) assumption that people are printing at the 'correct' size (and obviously handle margins correctly so that I don’t need to handle separate styles for US and ISO paper sizes).I use 100% for the
bodyelement, and relative units for everything else—mainly REM. Most of the clients I do work for require that their sites are accessible, which means I need to ensure the sites meet WCAG requirements.There’s this really good article on 24 Accessibility on this subject by Kathleen McMahon which showcases side-by-side examples of what happens, including this one below, where a user sets their font size to "Very large" in Chrome:
This image shows the following:
font-sizeand the fixedline-heightproperties, thus does not resize according to user preference.line-heightis set in pixels the paragraph text is visually squashed together.REM is a bit more work to implement, but it goes a long way for the user.
This right here.
We went through 6+ phases over the years... AND we're back to
pxfor the font-sizes.. but we useemfor letter-spacing andno unitfor line-height... and well, it depends. Sometimes we think about opening up the discussion again... but - mostempeople can't make their argument. We also useclamp()a lot now - (but mostly with vmin and px...I recently switched mainly to REM, only using pixels for borders and media queries.
yah
rema lot for media querie.Using
remfor everything other than media queries.Yes! I am the FIRST!
On web I prefer rems, but will modify the 16px baseline depending on client needs (like font sizes that adjust based on display width).
Usually pixels if I'm making an Electron application that's on a fixed device screen size and doesn't need to support multiple devices.
Testing has always been a part of my development process its to be expected when you are building a website. Working with pixels is exactly the same it is not limited to
rem. Some developers preferremwhereas some prefer pixels as you can see from this discussion. Thats the great thing about being a developer the freedom of choice. 🙂I back you Andrew, I use rem for everything. Fonts, margins, padding, width, height. Scales better with respnsiveness