diff --git a/requirements.txt b/requirements.txt
index a5a9c7a..164fb50 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,6 @@ babel==2.10.3
 black==22.10.0
 certifi==2022.9.24
 cfgv==3.3.1
-charset-normalizer==2.1.1
 click==8.1.3
 coverage==6.5.0
 git+https://github.com/DiamondLightSource/diffcalc-core.git#egg=diffcalc-core