diff --git a/index.js b/index.js
index a742002..4c0da31 100644
--- a/index.js
+++ b/index.js
@@ -1,12 +1,15 @@
 var assert = require('assert')
-var CryptoJS = require('crypto-js')
 var crypto = require('crypto')
+var pbkdf2 = require('pbkdf2-compat')
 
 var DEFAULT_WORDLIST = require('./wordlists/en.json')
 
+function mnemonicToSeed(mnemonic, password) {
+  return pbkdf2(mnemonic, salt(password), 2048, 64, 'sha512')
+}
+
 function mnemonicToSeedHex(mnemonic, password) {
-  var options = { iterations: 2048, hasher: CryptoJS.algo.SHA512, keySize: 512/32 }
-  return CryptoJS.PBKDF2(mnemonic, salt(password), options).toString(CryptoJS.enc.Hex)
+  return mnemonicToSeed(mnemonic, password).toString('hex')
 }
 
 function mnemonicToEntropy(mnemonic, wordlist) {
@@ -113,6 +116,7 @@ function lpad(str, padString, length) {
 }
 
 module.exports = {
+  mnemonicToSeed: mnemonicToSeed,
   mnemonicToSeedHex: mnemonicToSeedHex,
   mnemonicToEntropy: mnemonicToEntropy,
   entropyToMnemonic: entropyToMnemonic,
diff --git a/package.json b/package.json
index 38c9ebd..d733547 100644
--- a/package.json
+++ b/package.json
@@ -21,8 +21,8 @@
   },
   "license": "ISC",
   "dependencies": {
-    "crypto-js": "^3.1.2-2",
-    "sinon": "^1.10.3"
+    "sinon": "^1.10.3",
+    "pbkdf2-compat": "^1.0.1"
   },
   "devDependencies": {
     "browserify": "^5.9.1",