# What units are \pgfphysicalheight and \pgfphysicalwidth defined in?

I often use \pgfphysicalheight and \pgfphysicalwidth from the pgfpages package to define sizes dynamically based on the dimensions of my page (which vary). For example, here's a "dynamic" vertical space:

\vspace*{.04\pgfphysicalheight}


What units are these pgf values actually in? In other words, what is the value of \pgfphysicalheight if my document height is 10in?

I found nothing in the pgfpages docs. Also tried logging the values with \show, but got something cryptic like "\dimen195" which I couldn't decipher further.

• use \showthe not \show – David Carlisle Apr 24 at 16:18

A TeX length (dimen or skip) register does not store the units used when the value is set, whether you use pt or cm or whatever is not recorded and it just saves the value as an integer which is the length in sp, if you look at the value using \the or \showthe then TeX will show the value using pt units (that is, the stored integer divided by 65536)

On the terminal you could see this for example by:

\$ latex
This is pdfTeX, Version 3.14159265-2.6-1.40.20 (TeX Live 2019) (preloaded format=latex)
restricted \write18 enabled.
**\relax
entering extended mode
LaTeX2e <2018-12-01>

*\textheight=10in

*\showthe\textheight
> 722.7pt.
<*> \showthe\textheight