diff --git a/README.md b/README.md
index 4e4c0f0..0921b2d 100644
--- a/README.md
+++ b/README.md
@@ -24,13 +24,13 @@ pip install -r requirements.txt
 
 You can generate an STL with the same name as the input file like this:
 
-```py
+```sh
 python svg2stl.py example.svg --thickness 4
 ```
 
 You can also show what this looks like in a GUI:
 
-```py
+```sh
 python svg2stl.py example.svg --thickness 4 --show
 ```