diff --git a/tox.ini b/tox.ini
index 2294f3a..284d06b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-minversion = 3.2.0
+minversion = 4.0.0
 envlist = linters,docs,py3
 skipsdist = True