Approximately Equal in LaTeX (\approx)

Where it is used

States that two values are approximately equal, such as a numerical estimate or a rounded constant.

Use \approx for numerical approximations like \pi \approx 3.14159 and for first-order expansions such as \sin x \approx x for small x. It is a relation, so TeX gives it thick spacing like =. Several look-alikes carry other meanings: \simeq often means asymptotically equal or isomorphic, \sim means asymptotic or distributed as, \cong denotes congruence or isomorphism, and \approxeq is a rarer variant. In finance and engineering texts, \approx usually marks rounded results; state the precision, for example to three decimal places, so readers know how loose the estimate is.

Also listed under: Relations & Comparisons, Currency & Finance

Minimal compilable example

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

\documentclass{article}
\begin{document}
Approximately Equal: $\approx$

\[ \pi \approx 3.14159, \quad \sqrt{2} \approx 1.414 \]
\end{document}

Related symbols

• Not Equal\neq
• Infinity\infty
• Less Than or Equal\leq
• Limit\lim_{x \to \infty}
• Greater Than or Equal\geq
• Integral\int_{a}^{b}

Frequently asked questions

How do I write Approximately Equal in LaTeX?

Type \approx in math mode, for example $\pi \approx 3.14159, \quad \sqrt{2} \approx 1.414$. It works in plain LaTeX without loading any package.

Which package do I need for \approx?

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

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

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