diff --git a/tox.ini b/tox.ini
index 5531c72e..770704ae 100644
--- a/tox.ini
+++ b/tox.ini
@@ -33,6 +33,6 @@ usedevelop = {[testenv:format]usedevelop}
 
 [testenv:docs]
 usedevelop = True
-commands = python -m sphinx -W doc/ doc/_build
+commands = python3 -m sphinx -W doc/ doc/_build
 deps =
   -r{toxinidir}/doc/requirements.txt