diff --git a/lodash.src.js b/lodash.src.js
index 2838f3fde..86cf2eea1 100644
--- a/lodash.src.js
+++ b/lodash.src.js
@@ -11558,7 +11558,7 @@
      * // => 10
      */
     function add(augend, addend) {
-      return augend + addend;
+      return (+augend || 0) + (+addend || 0);
     }
 
     /**