diff --git a/Algorithms/symmetricDifference.js b/Algorithms/symmetricDifference.js
new file mode 100644
index 0000000..93d0034
--- /dev/null
+++ b/Algorithms/symmetricDifference.js
@@ -0,0 +1,21 @@
+// https://www.freecodecamp.org/learn/coding-interview-prep/algorithms/find-the-symmetric-difference
+
+function sym() {
+  const symDiff = {};
+  for (let [_, arr] of Object.entries(arguments)) {
+    const set = {};
+    arr.forEach((e) => {
+      set[e] = true;
+    });
+    for (let [e, _] of Object.entries(set)) {
+      if (symDiff[e]) {
+        delete symDiff[e];
+      } else {
+        symDiff[e] = true;
+      }
+    }
+  }
+  return Object.keys(symDiff).map((e) => Number(e));
+}
+
+console.log(sym([1, 2, 3, 3], [5, 2, 1, 4]));