diff --git a/index.js b/index.js
index 7d22e68..ea345c0 100644
--- a/index.js
+++ b/index.js
@@ -14,7 +14,7 @@ function plugin(options) {
 
   options = options || {};
 
-  if (!options.canonicalUris) {
+  if (typeof options.canonicalUris === 'undefined') {
     options.canonicalUris = true;
   }