diff --git a/django/newforms/fields.py b/django/newforms/fields.py
index c18de0f35b..58b46ce2b8 100644
--- a/django/newforms/fields.py
+++ b/django/newforms/fields.py
@@ -113,9 +113,9 @@ class CharField(Field):
         value = smart_unicode(value)
         value_length = len(value)
         if self.max_length is not None and value_length > self.max_length:
-            raise ValidationError(ugettext(u'Ensure this value has at most %d characters (it has %d).') % (self.max_length, value_length))
+            raise ValidationError(ugettext(u'Ensure this value has at most %(max)d characters (it has %(length)d).') % {'max': self.max_length, 'length': value_length})
         if self.min_length is not None and value_length < self.min_length:
-            raise ValidationError(ugettext(u'Ensure this value has at least %d characters (it has %d).') % (self.min_length, value_length))
+            raise ValidationError(ugettext(u'Ensure this value has at least %(min)d characters (it has %(length)d).') % {'min': self.min_length, 'length': value_length})
         return value
 
     def widget_attrs(self, widget):