sheets.rows.cells.fontSize Number (default: 11)

Sets the font size in pixels.

Example - setting the font size

<script>
var workbook = new kendo.ooxml.Workbook({
  sheets: [
      {
          rows: [
            { cells: [ { value: "20px", fontSize: 20 } ] }
          ]
      }
  ]
});
workbook.toDataURLAsync().then(function(dataURL) {
  kendo.saveAs({
    dataURI: dataURL,
    fileName: "Test.xlsx"
  });
});
</script>