diff --git a/composer.json b/composer.json
index 54b97320..e2995543 100644
--- a/composer.json
+++ b/composer.json
@@ -11,7 +11,8 @@
         "ext-fileinfo": "*",
         "monolog/monolog": "^2.2",
         "guzzlehttp/guzzle": "^7.0",
-        "composer/ca-bundle": "^1.3"
+        "composer/ca-bundle": "^1.3",
+        "ramsey/uuid": "^4.7"
     },
     "require-dev": {
         "squizlabs/php_codesniffer": "3.*",
diff --git a/src/Handlers/HMAC/Generator.php b/src/Handlers/HMAC/Generator.php
index 15dea58e..e2c1fc91 100644
--- a/src/Handlers/HMAC/Generator.php
+++ b/src/Handlers/HMAC/Generator.php
@@ -21,6 +21,7 @@
 namespace Buckaroo\Handlers\HMAC;
 
 use Buckaroo\Config\Config;
+use Ramsey\Uuid\Uuid;
 
 class Generator extends Hmac
 {
@@ -67,7 +68,7 @@ public function __construct(Config $config, $data, $uri, $method = 'POST')
 
         $this->base64Data($data);
         $this->uri($uri);
-        $this->nonce('nonce_' . rand(0000000, 9999999));
+        $this->nonce(Uuid::uuid4());
         $this->time(time());
     }