Rules / Output

LaTeX Warning: Label `…' multiply defined — Label defined twice

Two \labels share a name, so references may point to the wrong place.

Fix

Give each label a unique name.

Example

Reproduced on TeX Live 2026 by CI · pdflatex · corpus/duplicate-label

Same label used twice

Fails: main.tex
\documentclass{article}
\begin{document}
\section{Method}\label{sec:method}
Text.
\section{Evaluation}\label{sec:method}
See Section~\ref{sec:method}.
\end{document}
Fixed
\documentclass{article}
\begin{document}
\section{Method}\label{sec:method}
Text.
\section{Evaluation}\label{sec:evaluation}
See Section~\ref{sec:method}.
\end{document}
What TeX prints in main.log
LaTeX Warning: Label `sec:method' multiply defined.