diff --git a/lib/bip32.js b/lib/bip32.js
index b5c34d1..a4e6876 100644
--- a/lib/bip32.js
+++ b/lib/bip32.js
@@ -140,12 +140,9 @@ BIP32.prototype.buildExtendedPublicKey = function() {
 
 BIP32.prototype.extendedPublicKeyString = function(format) {
   if (format === undefined || format === 'base58') {
-    var hash = Hash.sha256sha256(this.extendedPublicKey);
-    var checksum = hash.slice(0, 4);
-    var data = Buffer.concat([this.extendedPublicKey, checksum]);
-    return base58.encode(data);
+    return Base58Check.encode(this.extendedPublicKey);
   } else if (format === 'hex') {
-    return this.extendedPublicKey.toString('hex');;
+    return this.extendedPublicKey.toString('hex');
   } else {
     throw new Error('bad format');
   }