Omega in LaTeX (\omega)

Where it is used

Lowercase Greek omega, used for angular frequency, sample outcomes, and the first infinite ordinal.

Physics writes angular frequency as \omega = 2\pi f, so a harmonic oscillator is x(t) = A\cos(\omega t + \varphi). Probability uses \omega \in \Omega for an outcome in the sample space, and set theory uses \omega for the first infinite ordinal. Complexity theory writes little-omega \omega(n) for strict lower bounds, and differential geometry uses \omega for differential forms. Number theory has \omega(n), the number of distinct prime factors. Be careful not to confuse \omega with the Latin w in handwritten notes.

Also listed under: Physics

Minimal compilable example

Paste this into an empty .tex file and compile it with pdfLaTeX, XeLaTeX or LuaLaTeX.

\documentclass{article}
\begin{document}
Omega: $\omega$

\[ x(t) = A \cos(\omega t + \varphi), \quad \omega = 2\pi f \]
\end{document}

Related symbols

• Omega (Upper)\Omega
• Psi (Upper)\Psi
• Psi\psi
• Chi\chi
• Phi (Upper)\Phi
• Phi\phi

Frequently asked questions

How do I write Omega in LaTeX?

Type \omega in math mode, for example $x(t) = A \cos(\omega t + \varphi), \quad \omega = 2\pi f$. It works in plain LaTeX without loading any package.

Which package do I need for \omega?

None. \omega is part of standard LaTeX, so it compiles with nothing in the preamble but the document class.

Can I use \omega in text mode, or only in math mode?

Only in math mode. Outside $...$ LaTeX stops with "Missing $ inserted", so write $\omega$ in running text. If you only need the glyph in text, paste the Unicode character ω instead (with XeLaTeX or LuaLaTeX and a font that has it).