TD column width value not working with fixed table-layout

The "archaic" width attribute does not take a unit, it expects something like width="20".

However, the "most correct" way to define a table is like so:

<table>
    <colgroup>
        <col style="width:20px" />
        <col style="width:50px" span="2" />
        <col style="width:15px" />
        <col style="width:25px" />
        <col style="width:20px" span="3" />
    </colgroup>
    <tbody>
        <tr>
            <td>col1</td>
            <td>col2</td>
            <td>col3</td>
            <td>col4</td>
            <td>col5</td>
            <td>col6</td>
            <td>col7</td>
            <td>col8</td>
        </tr>
    </tbody>
</table>

This works especially well for large tables, because the browser only needs to read the <colgroup> element to know exactly how the entire table should be laid out, without needing to calculate widths based on individual cell styles.

You have to use:

<td width="20">

or

<td style="width: 20px">