> For the complete documentation index, see [llms.txt](https://notes.eliasnorrby.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://notes.eliasnorrby.com/css/units-to-use.md).

# Which unit to use?

* For **typography**, use `rem`
* For **box model properties** (`margin`/`padding`/`border`), use `px`
* For `width`/`height`, use `%` or `px`
* For `color`, use `hsl`