diff --git a/setup.py b/setup.py
index 0662a7f..902840e 100755
--- a/setup.py
+++ b/setup.py
@@ -187,7 +187,7 @@ extras_require = dict(
     terminal = [],
     kernel = ['ipykernel'],
     nbformat = ['nbformat'],
-    notebook = ['notebook'],
+    notebook = ['notebook', 'ipywidgets'],
     nbconvert = ['nbconvert'],
 )
 install_requires = [