diff --git a/src/utils/Browser.js b/src/utils/Browser.js
deleted file mode 100644
index cd13e027..00000000
--- a/src/utils/Browser.js
+++ /dev/null
@@ -1,22 +0,0 @@
-/**
- * Attributes and methods to help with identifying the current browser and platform.
- * @module xterm/utils/Browser
- * @license MIT
- */
-
-import { contains } from './Generic.js';
-
-let isNode = (typeof navigator == 'undefined') ? true : false;
-let userAgent = (isNode) ? 'node' : navigator.userAgent;
-let platform = (isNode) ? 'node' : navigator.platform;
-
-export let isFirefox = !!~userAgent.indexOf('Firefox');
-export let isMSIE = !!~userAgent.indexOf('MSIE') || !!~userAgent.indexOf('Trident');
-
-// Find the users platform. We use this to interpret the meta key
-// and ISO third level shifts.
-// http://stackoverflow.com/q/19877924/577598
-export let isMac = contains(['Macintosh', 'MacIntel', 'MacPPC', 'Mac68K'], platform);
-export let isIpad = platform === 'iPad';
-export let isIphone = platform === 'iPhone';
-export let isMSWindows = contains(['Windows', 'Win16', 'Win32', 'WinCE'], platform);
diff --git a/src/utils/Browser.ts b/src/utils/Browser.ts
new file mode 100644
index 00000000..04da698e
--- /dev/null
+++ b/src/utils/Browser.ts
@@ -0,0 +1,22 @@
+/**
+ * Attributes and methods to help with identifying the current browser and platform.
+ * @module xterm/utils/Browser
+ * @license MIT
+ */
+
+import { contains } from './Generic';
+
+const isNode = (typeof navigator === 'undefined') ? true : false;
+const userAgent = (isNode) ? 'node' : navigator.userAgent;
+const platform = (isNode) ? 'node' : navigator.platform;
+
+export const isFirefox = !!~userAgent.indexOf('Firefox');
+export const isMSIE = !!~userAgent.indexOf('MSIE') || !!~userAgent.indexOf('Trident');
+
+// Find the users platform. We use this to interpret the meta key
+// and ISO third level shifts.
+// http://stackoverflow.com/q/19877924/577598
+export const isMac = contains(['Macintosh', 'MacIntel', 'MacPPC', 'Mac68K'], platform);
+export const isIpad = platform === 'iPad';
+export const isIphone = platform === 'iPhone';
+export const isMSWindows = contains(['Windows', 'Win16', 'Win32', 'WinCE'], platform);
diff --git a/src/utils/Generic.js b/src/utils/Generic.ts
similarity index 88%
rename from src/utils/Generic.js
rename to src/utils/Generic.ts
index 42f876f3..ce09c1be 100644
--- a/src/utils/Generic.js
+++ b/src/utils/Generic.ts
@@ -9,6 +9,6 @@
  * @param {Array} array The array to search for the given element.
  * @param {Object} el The element to look for into the array
  */
-export let contains = function(arr, el) {
+export function contains(arr: any[], el: any) {
   return arr.indexOf(el) >= 0;
 };