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Answer : There is the physics package: \documentclass{article} \usepackage{physics} \begin{document} $\bra{\Psi}\ket{\Psi}$ $\expval{A}{\Psi}$ \end{document} It offers many other goodies for typsetting physics things. Details can be found in the manul ( texdoc physics from command prompt/terminal). Use \braket{0|0} : \documentclass{standalone} \usepackage{braket} \begin{document} $\braket{0|0}$ \end{document} A solution using the mathtools package: \documentclass{article} \usepackage{mathtools} \DeclarePairedDelimiter\bra{\langle}{\rvert} \DeclarePairedDelimiter\ket{\lvert}{\rangle} \DeclarePairedDelimiterX\braket[2]{\langle}{\rangle}{#1 \delimsize\vert #2} \begin{document} \begin{align*} \bra{a} &= \bra*{\frac{a}{1}} \\ \ket{a} &= \ket*{\frac{a}{1}} \\ \braket{a}{b} &= \braket*{\frac{a}{1}}{\frac{b}{1}} \end{align*} \end{document} Notice that the starred versions of the macros scale automatically.