LaTeX/Fonts & Font families

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There are hundreds - if not thousands - of typefaces, or font families. Common examples include Times, Courier, and Helvetica. These families can generally be grouped into three main categories: serif, sans serif, and monospaced. LaTeX commands generally refer to these with the shorthand rm, sf, and tt respectively.

By default, LaTeX uses Computer Modern, a family of typefaces designed by Donald Knuth for use with TeX. It contains serif, sans serif, and monospaced fonts, each available in several weights and optical sizes.

Font styles

Typefaces usually come in various styles and weights, such as italic and bold. The following table lists the commands you will need to access typical font shapes.

LaTeX command	Equivalent switch	Output style	Remarks
\textnormal{...}	{\normalfont ...}	$\text{document font family}$	This is the default or normal font.
\textrm{...}	{\rmfamily ...}	$\text{roman font family}$
\textsf{...}	{\sffamily ...}	$\mathsf{\text{sans serif font family}}$
\texttt{...}	{\ttfamily ...}	$\mathtt{\text{teletypefont family}}$	This is a fixed-width or monospace font.
\textit{...}	{\itshape ...}	$\mathit{\text{italic shape}}$
\textbf{...}	{\bfseries ...}	$\mathbf{\text{bold}}$

Generally, one should prefer the commands over their equivalent switches because the former automatically corrects spacing immediately following the end of the selected style.

You may have noticed the absence of underline - this is because underlining is a byproduct of the typewriter era, and is not recommended when bold and italic type is available instead. However, underlining can be useful in some cases, such as to draw attention to changes during editing. Although underlining is available via the \underline{...} command, text underlined in this way will not break properly.

Sizing text

Built-in sizes

To scale text relative to the default body text size, use the following commands:

Command	Output
\tiny	$sampletext$
\scriptsize	$sampletext$
\small	$sampletext$
\normalsize	$sampletext$
\large	$sampletext$
\Large	$sampletext$
\LARGE	$sampletext$
\huge	$sampletext$
\Huge	$sampletext$

These commands change the size within a given scope. For instance \Large{some words} will change the size of only some words, and does not affect the font in the rest of the document. It will work for most parts of the text.

By default, \normalsize is 10 points. Note that not every document class has unique sizes for all of the above size commands.

Absolute Point Sizes

size	standard classes (except slides), beamer			AMS classes, memoir			slides
	[10pt]	[11pt]	[12pt]	[10pt]	[11pt]	[12pt]
\tiny	5	6	6	6	7	8	13.82
\scriptsize	7	8	8	7	8	9	16.59
\small	9	10	10.95	9	10	10.95	16.59
\normalsize	10	10.95	12	10	10.95	12	19.907
\large	12	12	14.4	10.95	12	14.4	23.89
\Large	14.4	14.4	17.28	12	14.4	17.28	28.66
\LARGE	17.28	17.28	20.74	14.4	17.28	20.74	34.4
\huge	20.74	20.74	24.88	17.28	20.74	24.88	41.28
\Huge	24.88	24.88	24.88	20.74	24.88	24.88	41.28

Points in TeX follow the standard American point system in which 1 pt is approximately 0.35136 mm. The standard point size used in most modern computer programs (known as the desktop publishing point or PostScript point) has 1 pt equal to approximately 0.3527 mm while the standard European point size (known as the Didot point) had 1 pt equal to approximately 0.37597151 mm.

Arbitrary sizes

The \tiny…\Huge commands are often enough for your needs, but you may occasionally want an arbitrary font size.This is done with \fontsize{<size>}{<line space>}\selectfont. For example:

\\fontsize{5cm}{5.5cm}\\selectfont

sets the current font size to 5cm with 5.5 centimeter leading.

If you are using the latex or pdflatex engines, you may get a warning similar to the following:

LaTeX Font Warning: Font shape `OT1/cmr/m/n' in size <142.26378> not available
(Font)              size <24.88> substituted on input line 103.

This is because these older engines only support a fixed set of sizes - between 5 and 17 point. When he designed Computer Modern, Knuth created individual font files for these sizes, each with stroke widths and spacing optimized for that particular size. To avoid distorting them, scaling these fonts is disabled by default.

This issue is avoided when using lualatex or xelatex, which use Latin Modern - a vectorized version of Computer Modern - as the default font family. This still provides individual files at each of the original optical sizes, but will automatically scale the closest one when asked for an arbitrary size.