diff --git a/probscale/tests/test_probscale.py b/probscale/tests/test_probscale.py
index 7f2b6f4..b056ee3 100644
--- a/probscale/tests/test_probscale.py
+++ b/probscale/tests/test_probscale.py
@@ -18,7 +18,7 @@
 if PY27:
     TOLERANCE = 25
 else:
-    TOLERANCE = 15
+    TOLERANCE = 22
 
 
 @pytest.fixture