diff --git a/bijoe/visualization/forms.py b/bijoe/visualization/forms.py
index 6a69000..8cb7c3c 100644
--- a/bijoe/visualization/forms.py
+++ b/bijoe/visualization/forms.py
@@ -102,8 +102,8 @@ class DateRangeWidget(forms.MultiWidget):
         attrs2 = attrs.copy()
         attrs2['placeholder'] = _(u'end')
         widgets = (
-            forms.DateInput(attrs=attrs1),
-            forms.DateInput(attrs=attrs2),
+            forms.DateInput(attrs=attrs1, format='%Y-%m-%d'),
+            forms.DateInput(attrs=attrs2, format='%Y-%m-%d'),
             forms.Select(choices=get_date_range_choices()),
         )
         super(DateRangeWidget, self).__init__(widgets, attrs=attrs)