Rules / Output

Overfull \hbox (…pt too wide) — Text in the margin

A line is wider than the text block by more than the threshold (default 10pt). The worst box per file is reported.

Fix

Rephrase, use \url/\path for long identifiers, or scale wide material to \linewidth.

Example

Reproduced on TeX Live 2026 by CI · pdflatex · corpus/overfull-hbox

Long unbreakable text sticks into the margin

Fails: main.tex
\documentclass{article}
\begin{document}
The configuration is read from the environment variable
\texttt{OVERFULL\_EXPERIMENT\_CONFIGURATION\_DIRECTORY\_OVERRIDE\_PATH} at start-up.
\end{document}
Fixed
\documentclass{article}
\usepackage{url}
\renewcommand{\UrlBreaks}{\do\_}
\begin{document}
\sloppy
The configuration is read from the environment variable
\path{OVERFULL_EXPERIMENT_CONFIGURATION_DIRECTORY_OVERRIDE_PATH} at start-up.
\end{document}
What TeX prints in main.log
Overfull \hbox (202.37006pt too wide) in paragraph at lines 3--5
[]\OT1/cmr/m/n/10 The con-fig-u-ra-tion is read from the en-vi-ron-ment vari-ab
le \OT1/cmtt/m/n/10 OVERFULL[]EXPERIMENT[]CONFIGURATION[]DIRECTORY[]OVERRIDE[]P
ATH
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