diff --git a/src/utils.js b/src/utils.js
index e8018ea..41d6368 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -29,7 +29,7 @@ module.exports = {
 
     if (Array.isArray(a)) {
       return !this.arraysDiffer(a, b);
-    } else if (typeof a === 'object' && a !== null) {
+    } else if (typeof a === 'object' && a !== null && a !== undefined) {
       return !this.objectsDiffer(a, b);
     }