Fit cell width to content

I'm not sure if I understand your question, but I'll take a stab at it:

td {
    border: 1px solid #000;
}

tr td:last-child {
    width: 1%;
    white-space: nowrap;
}

<table style="width: 100%;">
    <tr>
        <td class="block">this should stretch</td>
        <td class="block">this should stretch</td>
        <td class="block">this should be the content width</td>
    </tr>
</table>

For me, this is the best autofit and autoresize for table and its columns (use css !important ... only if you can't without)

.myclass table {
    table-layout: auto !important;
}

.myclass th, .myclass td, .myclass thead th, .myclass tbody td, .myclass tfoot td, .myclass tfoot th {
    width: auto !important;
}

Don't specify css width for table or for table columns. If table content is larger it will go over screen size to.

There are many ways to do this!

correct me if I'm wrong but the question is looking for this kind of result.

<table style="white-space:nowrap;width:100%;">
  <tr>
    <td class="block" style="width:50%">this should stretch</td>
    <td class="block" style="width:50%">this should stretch</td>
    <td class="block" style="width:auto">this should be the content width</td>
  </tr>
</table>

The first 2 fields will "share" the remaining page (NOTE: if you add more text to either 50% fields it will take more space), and the last field will dominate the table constantly.

If you are happy to let text wrap you can move white-space:nowrap; to the style of the 3rd field
will be the only way to start a new line in that field.

alternatively, you can set a length on the last field ie. width:150px, and leave percentage's on the first 2 fields.

Hope this helps!

Setting

max-width:100%;
white-space:nowrap;

will solve your problem.