diff --git a/index.js b/index.js
index 3052c5e..e97bc91 100644
--- a/index.js
+++ b/index.js
@@ -56,9 +56,9 @@ hotp.gen = function(key, opt) {
 	var p = 6;
 
 	// Create the byte array
-	var b = new Buffer(intToBytes(counter));
+	var b = Buffer.from(intToBytes(counter));
 
-	var hmac = crypto.createHmac('sha1', new Buffer(key));
+	var hmac = crypto.createHmac('sha1', Buffer.from(key));
 
 	// Update the HMAC with the byte array
 	var digest = hmac.update(b).digest('hex');