Tilde in LaTeX

Three ways to use the tilde in LaTeX: \sim (∼), \tilde{x} (x̃), and \widetilde{xyz} (x͂yz).

$\sim$              % standalone tilde: ∼
$\tilde{x}$        % tilde accent over one letter
$\widetilde{xyz}$  % wide tilde over multiple letters

Standalone Tilde: \sim

Use \sim (short for "similar") to render a standalone tilde symbol. It must be inside a math environment.

\documentclass{article}
\begin{document}

This text contains a tilde $\sim$ as a standalone symbol.

In math: $\pi \sim 3$, meaning pi is approximately 3.

\end{document}

Why not just type ~? In LaTeX, a bare tilde is a non-breaking space — it connects words without allowing a line break there. It will not produce the tilde symbol.

Tilde Accent: \tilde{}

\tilde{} places a tilde accent over a single character. This is commonly used in mathematics for estimated or transformed variables.

$\tilde{x}$     % x with tilde: x̃
$\tilde{\mu}$   % mu with tilde
$\tilde{X}$     % capital X with tilde

Wide Tilde: \widetilde{}

\widetilde{} stretches the tilde to span multiple characters — useful for indicating the approximation of a whole expression.

$\widetilde{xyz}$       % tilde over xyz
$\widetilde{f(x)}$     % tilde over f(x)
$\widetilde{A + B}$    % tilde over A+B

Approximately Equal: \approx

When you mean "approximately equal to" (≈), use \approx rather than \sim. The two are related but distinct in mathematical writing.

$a \sim b$      % a is distributed like b (statistics)
$a \approx b$  % a is approximately equal to b

Non-Breaking Space

A bare tilde ~ in LaTeX source is a non-breaking space. This is useful for keeping a number and its unit together, or a name and its title.

Dr.~Smith will present the results on page~42.
% Prevents line breaks between "Dr." and "Smith", and between "page" and "42".

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