diff --git a/requirements_dev.txt b/requirements_dev.txt
index bed373f..824eff2 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -4,4 +4,4 @@ flake8==3.7.9
 pytest==5.3.1
 pytz==2019.3
 Sphinx==2.2.2
-tox==3.14.2
+tox==4.23.2