<script>
var workbook = new kendo.ooxml.Workbook({
  sheets: [
      {
          rows: [
            { cells: [ { value: "John" }, { value: "Doe" } ] },
            { cells: [ { value: "Jane" }, { value: "Doe" } ] }
          ]
      }
  ]
});
workbook.toDataURLAsync().then(function(dataURL) {
  kendo.saveAs({
    dataURI: dataURL,
    fileName: "Test.xlsx"
  });
});
</script>