> 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/knowledge-base/026-changing-compiler.md).

# Changing compiler

Sometimes for certain languages, classes and packages it may be necessary to use a different compiler than the default **`pdflatex`**. With Overleaf, you can choose between pdfLaTeX, LaTeX, XƎLaTeX, and LuaLaTeX.

To change the compiler:

1. Select the left-hand menu:

![Lefthandmenu.PNG](/files/N069lBukH6jO54osMq5e)

3. Select the **Compiler** drop-down list (located under **Settings**):

![Compiler.png](/files/ow4UujoVKnMlqiiBsDNB)


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