diff --git a/.travis.yml b/.travis.yml
index d4dedd6..296bd19 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ node_js:
   - "0.12"
   - "4"
   - "5"
+  - "6"
 env:
   matrix:
     - TEST_SUITE=unit
diff --git a/index.js b/index.js
index 9cd6a70..914af68 100644
--- a/index.js
+++ b/index.js
@@ -41,7 +41,7 @@ HashBase.prototype._flush = function (callback) {
 HashBase.prototype.update = function (data, encoding) {
   if (!Buffer.isBuffer(data) && typeof data !== 'string') throw new TypeError('Data must be a string or a buffer')
   if (this._finalized) throw new Error('Digest already called')
-  if (!Buffer.isBuffer(data)) data = new Buffer(data, encoding || 'binary')
+  if (!Buffer.isBuffer(data)) data = new Buffer(data, encoding)
 
   // consume data
   var block = this._block
diff --git a/test/index.js b/test/index.js
index 5cd9c93..18798d1 100644
--- a/test/index.js
+++ b/test/index.js
@@ -1,5 +1,5 @@
 'use strict'
-var test = require('tape').test
+var test = require('tape')
 var HashBase = require('../')
 
 function beforeEach (t) {
@@ -87,11 +87,13 @@ test('update', function (t) {
     t.end()
   })
 
-  t.test('decode string with binary by default', function (t) {
+  t.test('decode string with utf8 by default', function (t) {
     t.plan(1)
     var buffer = new Buffer(64)
+    buffer.fill(0)
+    new Buffer('УТФ-8', 'utf8').copy(buffer)
     t.base._update = function () { t.same(this._block, buffer) }
-    t.base.update(buffer.toString('binary'))
+    t.base.update(buffer.toString('utf8'))
     t.end()
   })