HTMLTableRowElement.insertCell()
  The HTMLTableRowElement.insertCell() method inserts a new
  cell (<td>) into a table row (<tr>) and returns a
  reference to the cell.
    Note: insertCell() inserts the cell directly into the
    row. The cell does not need to be appended separately
    with Node.appendChild() as would be the case if
    Document.createElement() had been used to create the new
    <td> element.
  
    You can not use insertCell() to create a new <th>
    element though.
  
Syntax
var newCell = HTMLTableRowElement.insertCell(index);
  HTMLTableRowElement is a reference to an HTML <tr>
  element.
Parameters
- indexOptional
- 
    The cell index of the new cell. If indexis-1or equal to the number of cells, the cell is appended as the last cell in the row. Ifindexis omitted it defaults to-1.
Return value
  An HTMLTableCellElement that references the new
  cell.
Exceptions
- IndexSizeError- DOMException
- 
    Thrown if indexis greater than the number of cells.
Example
  This example uses HTMLTableElement.insertRow() to append a new row to a
  table.
  We then use insertCell(0) to insert a new cell in the new row. (To be
  valid HTML, a <tr> must have at least one <td>
  element.) Finally, we add some text to the cell using
  Document.createTextNode() and Node.appendChild().
HTML
<table id="my-table">
  <tr><td>Row 1</td></tr>
  <tr><td>Row 2</td></tr>
  <tr><td>Row 3</td></tr>
</table>
JavaScript
function addRow(tableID) {
  // Get a reference to the table
  let tableRef = document.getElementById(tableID);
  // Insert a row at the end of the table
  let newRow = tableRef.insertRow(-1);
  // Insert a cell in the row at index 0
  let newCell = newRow.insertCell(0);
  // Append a text node to the cell
  let newText = document.createTextNode('New bottom row');
  newCell.appendChild(newText);
}
// Call addRow() with the table's ID
addRow('my-table');
Result
Specifications
| Specification | 
|---|
| HTML Standard # dom-tr-insertcell-dev | 
Browser compatibility
BCD tables only load in the browser
See also
- HTMLTableElement.insertRow()
- The HTML element representing cells: HTMLTableCellElement