diff --git a/src/ReactHTMLTableToExcel.jsx b/src/ReactHTMLTableToExcel.jsx
index fd32011..4d66866 100644
--- a/src/ReactHTMLTableToExcel.jsx
+++ b/src/ReactHTMLTableToExcel.jsx
@@ -50,7 +50,7 @@ class ReactHTMLTableToExcel extends Component {
 
     const table = document.getElementById(this.props.table).outerHTML;
     const sheet = String(this.props.sheet);
-    const filename = `${String(this.props.filename)}.xls`;
+    const filename = `${String(this.props.filename)}.xlsx`;
 
     const uri = 'data:application/vnd.ms-excel;base64,';
     const template =