> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/questions-and-answers/66-i-m-trying-to-include-urls-in-my-.tex-or-.bib-but-i-got-an-error-missing-inserted.md).

# I'm trying to include URLs in my .tex or .bib, but I got an error "Missing $ inserted"

Your URL might be containing some underscore characters `_`, which are special characters in LaTeX — they're the subscript operator when in math mode, e.g. `$x_i$` will produce $$x\_i$$. Usually, if you want to use a literal underscore character in normal text, you'll have to write escape it as `\_`.

Fortunately there's an easier way to include URLs with underscores. If you add `\usepackage{url}` or `\usepackage{hyperref}` just before your `\begin{document}`, you can then write:

```latex
\url{https://www.example.com/url_with_underscore}
```

in your document.

For further details, refer to the Overleaf help article [Missing $ inserted](/latex/latex-errors/25-missing-inserted.md).


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