> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/mathematics/12-mathematical-fonts.md).

# Mathematical fonts

## Introduction

Some mathematical elements need to be typeset using fonts containing characters/symbols of a certain style; for example, it is customary to represent real numbers with a blackboard bold font (such as $$\mathbb{R}$$), or topological spaces with calligraphic font (such as ($$\mathcal{T}$$). This article shows how to use different font styles when typesetting mathematics, starting with the following example:

```latex
Let \( \mathcal{T} \) be a topological space, a basis is defined as
\[
 \mathcal{B} = \{B_{\alpha} \in \mathcal{T}\, |\,  U = \bigcup B_{\alpha} \forall U \in \mathcal{T} \}
\]
```

[Open this example in Overleaf](https://www.overleaf.com/docs?engine=pdflatex\&snip_name=Maths+typeface+example\&snip=%5Cdocumentclass%7Barticle%7D%0A%5Cbegin%7Bdocument%7D%0ALet+%5C%28+%5Cmathcal%7BT%7D+%5C%29+be+a+topological+space%2C+a+basis+is+defined+as%0A%5C%5B%0A+%5Cmathcal%7BB%7D+%3D+%5C%7BB_%7B%5Calpha%7D+%5Cin+%5Cmathcal%7BT%7D%5C%2C+%7C%5C%2C++U+%3D+%5Cbigcup+B_%7B%5Calpha%7D+%5Cforall+U+%5Cin+%5Cmathcal%7BT%7D+%5C%7D%0A%5C%5D%0A%5Cend%7Bdocument%7D)

This example produces the following output:

![Math fonts example](/files/HpdhcvrVYXgIZfUWKMaM)

Use of some math font styles requires the line `\usepackage{amssymb}` to be added to the document preamble: see the [`amsfonts` package](https://ctan.org/pkg/amsfonts) for further information.

## Capital letters-only font typefaces

There are some font typefaces which support only a limited number of characters; these fonts usually denote some special sets. For instance, to display the R in blackboard bold typeface you can use `\(\mathbb{R}\)` to produce $$\mathbb{R}$$. The following example shows calligraphic, fraktur and blackboard bold typefaces:

```latex
\documentclass{article}
\usepackage{amsmath}
\usepackage{amssymb}
\begin{document}
\begin{align*}
RQSZ \\
\mathcal{RQSZ} \\
\mathfrak{RQSZ} \\
\mathbb{RQSZ}
\end{align*}
\end{document}
```

[Open this example in Overleaf](https://www.overleaf.com/docs?engine=pdflatex\&snip_name=Using+different+math+fonts\&snip=%5Cdocumentclass%7Barticle%7D%0A%5Cusepackage%7Bamsmath%7D%0A%5Cusepackage%7Bamssymb%7D%0A%5Cbegin%7Bdocument%7D%0A%5Cbegin%7Balign%2A%7D%0ARQSZ+%5C%5C%0A%5Cmathcal%7BRQSZ%7D+%5C%5C%0A%5Cmathfrak%7BRQSZ%7D+%5C%5C%0A%5Cmathbb%7BRQSZ%7D%0A%5Cend%7Balign%2A%7D%0A%5Cend%7Bdocument%7D)

This example produces the following output:

![Changing fonts for typesetting maths](/files/uKdvwcZHcSecTNabYZZd)

## Other mathematical fonts

It is possible to set a different font family for a complete mathematical expression:

```latex
\begin{align*}
3x^2 \in R \subset Q \\
\mathnormal{3x^2 \in R \subset Q} \\
\mathrm{3x^2 \in R \subset Q} \\
\mathit{3x^2 \in R \subset Q} \\
\mathbf{3x^2 \in R \subset Q} \\
\mathsf{3x^2 \in R \subset Q} \\
\mathtt{3x^2 \in R \subset Q}
\end{align*}
```

[Open this example in Overleaf](https://www.overleaf.com/docs?engine=pdflatex\&snip_name=Using+a+font+family+for+mathematical+expressions\&snip=%5Cdocumentclass%7Barticle%7D%0A%5Cusepackage%7Bamsmath%7D%0A%5Cusepackage%7Bamssymb%7D%0A%5Cbegin%7Bdocument%7D%0A%5Cbegin%7Balign%2A%7D%0A3x%5E2+%5Cin+R+%5Csubset+Q+%5C%5C%0A%5Cmathnormal%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D+%5C%5C%0A%5Cmathrm%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D+%5C%5C%0A%5Cmathit%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D+%5C%5C%0A%5Cmathbf%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D+%5C%5C%0A%5Cmathsf%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D+%5C%5C%0A%5Cmathtt%7B3x%5E2+%5Cin+R+%5Csubset+Q%7D%0A%5Cend%7Balign%2A%7D%0A%5Cend%7Bdocument%7D)

This example produces the following output:

![Changing fonts for typesetting maths](/files/yuVx3RHY5GeMCQp6vl6T)

In this case, not only letters but all characters change their appearance; for example, `$\mathit{3x^2}$` italicises the entire expression to produce $$\mathit{3x^2}$$.

## Further reading

For more information see

* [`amsfonts` package documentation](https://ctan.org/pkg/amsfonts)
* [Mathematical expressions](/latex/mathematics/01-mathematical-expressions.md)
* [Subscripts and superscripts](/latex/mathematics/02-subscripts-and-superscripts.md)
* [Bold, italics and underlining](/latex/latex-basics/03-bold-italics-and-underlining.md)
* [Font sizes, families, and styles](/latex/fonts/01-font-sizes-families-and-styles.md)
* [Font typefaces](/latex/fonts/02-font-typefaces.md)
* [Text alignment](/latex/formatting/06-text-alignment.md)
* [The not so short introduction to LaTeX2ε](http://www.ctan.org/tex-archive/info/lshort/)


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