diff --git a/src/DayPicker.js b/src/DayPicker.js
index <HASH>..<HASH> 100644
--- a/src/DayPicker.js
+++ b/src/DayPicker.js
@@ -25,6 +25,7 @@ class Caption extends Component { // eslint-disable-line
 }
 
 export default class DayPicker extends Component {
+  static VERSION = "2.0.0";
 
   static propTypes = {
     tabIndex: PropTypes.number,
Add version number to DayPicker class

This can be helpful if you need to figure out what version of a library is actually running in your app.