diff --git a/lib.es5/node/base64.js b/lib.es5/node/base64.js
index 59776c39..dc78d960 100644
--- a/lib.es5/node/base64.js
+++ b/lib.es5/node/base64.js
@@ -4,11 +4,17 @@
 Object.defineProperty(exports, "__esModule", {
   value: true
 });
+exports.isSupported = undefined;
 exports.encode = encode;
-/* global: Buffer */
+
+var _bufferFrom = require("buffer-from");
+
+var _bufferFrom2 = _interopRequireDefault(_bufferFrom);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
 
 function encode(data) {
-  return new Buffer(data).toString("base64");
+  return (0, _bufferFrom2.default)(String(data)).toString("base64");
 }
 
 var isSupported = exports.isSupported = true;
\ No newline at end of file
diff --git a/lib/node/base64.js b/lib/node/base64.js
index 30d21414..5003cf20 100644
--- a/lib/node/base64.js
+++ b/lib/node/base64.js
@@ -1,7 +1,7 @@
-/* global: Buffer */
+import bufferFrom from "buffer-from";
 
 export function encode(data) {
-  return new Buffer(data).toString("base64");
+  return bufferFrom(String(data)).toString("base64");
 }
 
 export const isSupported = true;
diff --git a/package.json b/package.json
index 633f9adc..acab73a7 100644
--- a/package.json
+++ b/package.json
@@ -53,6 +53,7 @@
     "watchify": "^3.5.0"
   },
   "dependencies": {
+    "buffer-from": "^0.1.1",
     "extend": "^3.0.0",
     "lodash.throttle": "^4.1.1",
     "resolve-url": "^0.2.1"
diff --git a/test/spec/upload.js b/test/spec/upload.js
index a905c034..87d9ceab 100644
--- a/test/spec/upload.js
+++ b/test/spec/upload.js
@@ -35,7 +35,8 @@ describe("tus", function () {
         metadata: {
           foo: "hello",
           bar: "world",
-          nonlatin: "słońce"
+          nonlatin: "słońce",
+          number: 100
         },
         withCredentials: true,
         onProgress: function () {},
@@ -57,7 +58,7 @@ describe("tus", function () {
       expect(req.requestHeaders["Upload-Length"]).toBe(11);
       if (isBrowser) expect(req.withCredentials).toBe(true);
       if (isNode || (isBrowser && "btoa" in window)) {
-        expect(req.requestHeaders["Upload-Metadata"]).toBe("foo aGVsbG8=,bar d29ybGQ=,nonlatin c8WCb8WEY2U=");
+        expect(req.requestHeaders["Upload-Metadata"]).toBe("foo aGVsbG8=,bar d29ybGQ=,nonlatin c8WCb8WEY2U=,number MTAw");
       }
 
       req.respondWith({