diff --git a/coding_interviews/algoexpert/product-sum/product-sum.js b/coding_interviews/algoexpert/product-sum/product-sum.js
new file mode 100644
index 0000000..9453306
--- /dev/null
+++ b/coding_interviews/algoexpert/product-sum/product-sum.js
@@ -0,0 +1,13 @@
+function productSum(array, product = 1) {
+  let sum = 0;
+
+  for (let num of array) {
+    if (Array.isArray(num)) {
+      sum += productSum(num, product + 1) * product;
+    } else {
+      sum += num * product;
+    }
+  }
+
+  return sum;
+}