LaTeX Font Size
Three layers of control: document-class option for the base size, ten size commands for inline overrides, and \fontsize + extsizes for anything non-standard.
The 10-second answer
% 1. Set base size in \documentclass
\documentclass[12pt]{article}
% 2. Inline size changes (scoped to braces)
{\large larger text}
{\small smaller text}
% 3. Custom size (works anywhere)
{\fontsize{14}{17}\selectfont fourteen-point text}
% 4. Non-standard base sizes
\documentclass[14pt]{extarticle}The 10 size commands (and what they actually produce)
The commands are relative — what they produce depends on the document class's base size:
| Command | 10pt class | 11pt class | 12pt class |
|---|---|---|---|
| \tiny | 5pt | 6pt | 6pt |
| \scriptsize | 7pt | 8pt | 8pt |
| \footnotesize | 8pt | 9pt | 10pt |
| \small | 9pt | 10pt | 11pt |
| \normalsize (default) | 10pt | 11pt | 12pt |
| \large | 12pt | 12pt | 14pt |
| \Large | 14pt | 14pt | 17pt |
| \LARGE | 17pt | 17pt | 20pt |
| \huge | 20pt | 20pt | 25pt |
| \Huge | 25pt | 25pt | 25pt |
Common patterns
Override section heading sizes
\usepackage{titlesec}
\titleformat{\section}{\Large\bfseries}{\thesection}{1em}{}
\titleformat{\subsection}{\large\bfseries}{\thesubsection}{1em}{}Document with 14pt body
\documentclass[14pt]{extarticle}
\usepackage[utf8]{inputenc}
\begin{document}
This document has a 14-point body.
\end{document}Mixed sizes inline
Normal body text.
{\small Smaller note in footnote-style.}
{\Large Important callout.}
Back to normal.Common mistakes
- Forgetting
\selectfontafter\fontsize.\fontsize{14}{17}alone does nothing. - Trying 14pt without extsizes. The standard
articleclass only accepts 10/11/12pt. Useextarticlefor other sizes. - Size leaking outside intended scope. Wrap with braces:
{\large text}, not\large text.
#set text(size: 14pt) // global
#text(size: 18pt)[heading] // inlineNo package juggling, no \selectfont. Try TypeTeX free.
Frequently Asked Questions
Pass it as a class option: \documentclass[12pt]{article}. The standard classes (article, report, book) accept 10pt (default), 11pt, and 12pt. Anything else (8pt, 14pt, 17pt, etc.) requires the extsizes package.
Use the extsizes package: \documentclass[14pt]{extarticle} (or extreport, extbook). Supports 8pt, 9pt, 10pt, 11pt, 12pt, 14pt, 17pt, and 20pt. For arbitrary sizes use \fontsize{14}{17}\selectfont — first number is point size, second is line spacing.
Use one of the size commands inside a group: {\small smaller text} or {\Large bigger text}. The braces scope the change so it doesn't bleed into the rest of the document. For multi-paragraph spans, use \begin{small} ... \end{small}.
\Large is bigger than \large (capital L), and \LARGE is bigger still (all caps). The full size hierarchy from smallest to largest: \tiny, \scriptsize, \footnotesize, \small, \normalsize, \large, \Large, \LARGE, \huge, \Huge.
\fontsize{13}{15.6}\selectfont — the second number (line spacing) is conventionally 1.2x the size. You must call \selectfont after \fontsize to actually apply the change. This works anywhere, even mid-paragraph.
Redefine \section, \subsection, etc., or use the titlesec package. Quick example: \usepackage{titlesec} \titleformat{\section}{\Large\bfseries}{\thesection}{1em}{}. This makes all \section headings render at \Large bold instead of the default.
Three common reasons: (1) you put it inside a group that ended (the braces { } limit scope); (2) you used \fontsize but forgot \selectfont; (3) a package or class is overriding it later. Test by adding the size command at the top of \begin{document} and seeing if it sticks.
Math typesetting uses three sizes automatically: text style (inline math), display style (full-size equations), and script style (subscripts/superscripts). Override with \displaystyle, \textstyle, \scriptstyle, or \scriptscriptstyle. To change all math sizes globally, use \DeclareMathSizes (advanced).
Yes. 12pt in LaTeX is 12pt in Word. The visual difference between LaTeX and Word at the same size comes from font choice (Computer Modern vs Calibri) and line spacing, not the point size itself.