# How do I set and get the correct font size?

I am working on a grant application that has to have 11pt font. I am using the following code and the research office is telling me the actual font is 10.9. How can I fix this issue?


\RequirePackage{fix-cm}
\documentclass[11pt,oneside]{article}
\usepackage{fontspec}
\setmainfont{Arial}
\defaultfontfeatures{Scale=MatchLowercase}
\defaultfontfeatures[\rmfamily]{Ligatures=Tex, Scale=1}
\nonfrenchspacing
\fontspec{texgyretermes-regular.otf}[WordSpace = 0.1]
\fontspec{texgyreschola-regular.otf}[PunctuationSpace=0]

\begin{document}

...

\end{document}



Many thanks. Cheers, Jason

• This is surprising since 1pt = 0.35146 mm and therefore 0.1pt = 0.035146 mm. I am not sure that a difference of three hundredths of a millimetre is detectable. What are the various units (ex, em, in, pt, bp, dd, pc) expressed in mm? – AndréC Jul 1 at 19:46
• @AndréC They are visually indistinguishable, but computers look at data and the PDF file advertises /F1 10.9091. – egreg Jul 1 at 19:57
• @egreg Interesting. How did you get this data from the PDF? – AndréC Jul 1 at 21:18
• @AndréC I asked qpdf to uncompress it. – egreg Jul 1 at 21:21
• @AndréC You can also run xelatex -output-driver="xdvipdfmx -z 0" <filename> and then look at the PDF file with a text editor. Font declaration start with /F<number>. qpdf is an external utility that can postprocess PDF files. – egreg Jul 1 at 21:29

Removing the useless bits and scaling the font

\documentclass[11pt,oneside]{article}
\usepackage{fontspec}
\setmainfont{Arial}[Scale=1.0084]

\begin{document}

ABC

\end{document}


The uncompressed PDF file says

stream
q 1 0 0 1 72 769.89 cm BT /F1 11.0008 Tf 70.735 -68.742 Td[<002400250026>]TJ 159.332 -558.307 Td[<0014>]TJ ET Q
endstream


so the font should be recognized as 11 (PostScript) points. The scale factor takes care of the fact that 11pt actually defines a font at 10.95pt and that PostScript has a somewhat larger point: 72 PostScript points equal 72.27 TeX points.

• "PostScript points" (72 per inch) are referred to in TeX lingo as bp ("big points"). Selecting a font at 11bp should be equivalent to this. – barbara beeton Jul 2 at 0:35
• @barbarabeeton it is at normalsize but scaling the font definition as here covers all of \large and \footnotesize etc at one go. – David Carlisle Jul 2 at 8:16