diff --git a/setup.py b/setup.py
index 895b413..da7d51b 100644
--- a/setup.py
+++ b/setup.py
@@ -59,6 +59,8 @@ setup(
         'Natural Language :: English',
         'Operating System :: OS Independent',
         'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: Implementation :: CPython',
diff --git a/tox.ini b/tox.ini
index 5b34146..aead7bb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py27, py34, py35, pypy, pypy3
+envlist = py27, py33, py34, py35, pypy, pypy3
 
 [testenv]
 commands =