setting font size

Question

I have a simple document and don't care about the details of sections and subsections, but I want a larger font size. I have

    \documentclass[20pt]{article}

but it doesn't enlarge the font in the main part of the document.

I have found a lot of complex answers that I do not understand; I just would like to know why I cannot set the font size in the documentclass, or if there is a way to do it after that.

The article documentclass only supports the font size options 10pt, 11pt and 12pt. — leandriis, Jun 25 '20 at 17:47
If you want to use a base font size between 8 and 20 pt, you can use the extarticle class instead. — leandriis, Jun 25 '20 at 17:47
the option is not a font size or a length it is just the name of an option. It sets many things including the text width as well as several font sizes. to select a larger font you can use eg \LARGE which is 22pt if you use the default 10pt option. — David Carlisle, Jun 25 '20 at 17:57

score 1 · Answer 1 · answered Jun 25 '20 at 21:02

You can select arbitrary font sizes with the Koma document classes, the scrextend package, or extsizes, A simple solution to your problem (which unfortunately is buried in the comments of answers to the canonical question) would be to add the line:

 \usepackage[fontsize=20pt]{scrextend}

You say, though, that you just want to know why you can’t write \documentclass[20pt]{article}. So, here’s a literal answer to the question you asked.

LaTeX does not parse package options as an arbitrary number followed by the letters p and t. There’s a fixed set of package options for backward compatibility, which go back to the days when Computer Modern was available in METAFONT in those specific optical sizes. Other packages, including the ones from KOMA-script, can and do provide key=value syntax for that.

setting font size

1 Answers1