diff --git a/requirements_dev.txt b/requirements_dev.txt
index 501db8b..0e1bf20 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -2,7 +2,7 @@ pip==20.1
 black==19.10b0
 bumpversion==0.5.3
 coverage==5.1
-tox==3.15.0
+tox==4.23.0
 wheel==0.34.2
 watchdog==0.10.2
 flake8==3.7.9