# Fraction in bookmarks [duplicate]

I have problem in bookmark. For example

\section{fraction $\frac{a}{b}$}


• Welcome to TeX.SE! Please show us a short, compilable code resulting in your issue and add the complete error message to your question. – Mensch Apr 8 '18 at 13:20

Bookmarks are simple text strings. Macro \texorpdfstring can be used to specify the outcome on a PDF page and the string for the bookmarks:
\documentclass{article}
\section{Fraction \texorpdfstring{$\frac{a}{b}$}{a/b}}