diff --git a/js/helpers.js b/js/helpers.js
index 03786a9a8..27cbd4209 100644
--- a/js/helpers.js
+++ b/js/helpers.js
@@ -423,7 +423,7 @@ window.textsecure.storage = function() {
             }
 
             while (groupId === undefined || textsecure.storage.getEncrypted("group" + groupId) !== undefined) {
-                groupId = new Uint32Array(textsecure.crypto.getRandomBytes(4))[0];
+                groupId = textsecure.crypto.getRandomBytes(16);
             }
 
 			var me = textsecure.utils.unencodeNumber(textsecure.storage.getUnencrypted("number_id"))[0];