<script>
var workbook = new kendo.ooxml.Workbook({
  sheets: [
      {
          name: "Sheet1",
          rows: [
              { cells: [ { value: "Header 1" }, { value: "Header 2" } ] },
              { cells: [ { value: "Data 1" }, { value: "Data 2" } ] }
          ]
      }
  ]
});

workbook.toDataURLAsync().then(function(dataURL) {
  kendo.saveAs({
    dataURI: dataURL,
    fileName: "workbook.xlsx"
  });
});
</script>