diff --git a/lib/formtastic-slug/slug_input.rb b/lib/formtastic-slug/slug_input.rb
index 8184d8f..e00e36c 100644
--- a/lib/formtastic-slug/slug_input.rb
+++ b/lib/formtastic-slug/slug_input.rb
@@ -47,7 +47,7 @@ class SlugInput < Formtastic::Inputs::StringInput
     var setSlug = function(text) {
       var i, k;
 
-      var originalSlug = text.toLowerCase().replace(/[^a-z0-9]+/g, '-');
+      var originalSlug = text.toLowerCase().replace(/[^a-z0-9]+/g, '-').replace(/^-|-$/, '');
       var newSlug = originalSlug;
       var index = 0;