What point (pt) font size are \Large etc.?

In the preamble I have:

\documentclass[a4paper,11pt]{article}
\usepackage{fontspec}
\setmainfont{Arial}


What can be inferred about the real font pt size for the following?

\tiny, \scriptsize, \footnotesize, \small, \normalsize, \large, \Large, \LARGE, \huge, \Huge

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If you want to be precise about font sizes, this answer might be of interest to you. – doncherry Aug 1 '11 at 11:22

The font changing commands are often determined by the document class itself. For the standard classes (with size options in the first row), the values are as follows:

Command             10pt    11pt    12pt
\tiny               5       6       6
\scriptsize         7       8       8
\footnotesize       8       9       10
\small              9       10      10.95
\normalsize         10      10.95   12
\large              12      12      14.4
\Large              14.4    14.4    17.28
\LARGE              17.28   17.28   20.74
\huge               20.74   20.74   24.88
\Huge               24.88   24.88   24.88


Other classes (especially the major document classes such as KOMA and Memoir) may have different values. The following document will print out the font sizes for all the standard size changing commands. You can use it to check font sizes for other classes.

\documentclass[11pt]{article}

\makeatletter
\newcommand\thefontsize[1]{{#1 The current font size is: \f@size pt\par}}
\makeatother

\begin{document}
\sffamily
\thefontsize\tiny
\thefontsize\scriptsize
\thefontsize\footnotesize
\thefontsize\small
\thefontsize\normalsize
\thefontsize\large
\thefontsize\Large
\thefontsize\LARGE
\thefontsize\huge
\thefontsize\Huge
\end{document}


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+1 for \f@size pt – fuenfundachtzig Aug 1 '11 at 14:34
doesn't work for LaTeX though :( – Frederick Nord May 2 at 22:38
@FrederickNord Of course it works with LaTeX. Just remove the XeLaTeX specific code from the sample document. I only used XeLaTeX because the original question used XeLaTeX. See Frequently loaded packages: Differences between pdfLaTeX and XeLaTeX. I've updated the code to work on any engine. – Alan Munn May 3 at 3:37

In classes.dtx: 6.1 Fonts.

Or size10.clo, size11.clo and size12.clo in \$TEXMF/tex/latex/base/.

For example, in size10.clo:

\newcommand\small{%
\@setfontsize\small\@ixpt{11}%
\abovedisplayskip 8.5\p@ \@plus3\p@ \@minus4\p@
\abovedisplayshortskip \z@ \@plus2\p@
\belowdisplayshortskip 4\p@ \@plus2\p@ \@minus2\p@
\def\@listi{\leftmargin\leftmargini
\topsep 4\p@ \@plus2\p@ \@minus2\p@
\parsep 2\p@ \@plus\p@ \@minus\p@
\itemsep \parsep}%
\belowdisplayskip \abovedisplayskip
}

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