diff --git a/src/main/java/io/voucherify/generator/VoucherCodes.java b/src/main/java/io/voucherify/generator/VoucherCodes.java
index 5b79439..bf78e92 100644
--- a/src/main/java/io/voucherify/generator/VoucherCodes.java
+++ b/src/main/java/io/voucherify/generator/VoucherCodes.java
@@ -1,10 +1,12 @@
 package io.voucherify.generator;
 
-import java.util.Random;
+import java.security.SecureRandom;
 
 public final class VoucherCodes {
 
-    private static final Random RND = new Random(System.currentTimeMillis());
+    private static final SecureRandom RND = new SecureRandom();
+    //preserve previous seed behavior (though not necessary, see https://docs.oracle.com/javase/8/docs/api/java/security/SecureRandom.html#SecureRandom--)
+    RND.setSeed(System.currentTimeMillis());
        
     /**
      * Generates a random code according to given config.