Two HTML tables side by side, centered on the page

Question

I have two tables on a page that I want to display side by side, and then center them within the page (actually within another div, but this is the simplest I could come up

Answer 1

If it was me - I would do with the table something like this:

<style type="text/css" media="screen">
  table {
    border: 1px solid black;
    float: left;
    width: 148px;
  }
  
  #table_container {
    width: 300px;
    margin: 0 auto;
  }
</style>

<div id="table_container">
  <table>
    <tr>
      <th>a</th>
      <th>b</th>
    </tr>
    <tr>
      <td>1</td>
      <td>2</td>
    </tr>
    <tr>
      <td>4</td>
      <td>9</td>
    </tr>
    <tr>
      <td>16</td>
      <td>25</td>
    </tr>
  </table>
  <table>
    <tr>
      <th>a</th>
      <th>b</th>
    </tr>
    <tr>
      <td>1</td>
      <td>2</td>
    </tr>
    <tr>
      <td>4</td>
      <td>9</td>
    </tr>
    <tr>
      <td>16</td>
      <td>25</td>
    </tr>
  </table>
</div>

Answer 2

Off the top of my head, you might try using the "margin: 0 auto" for #outer rather than #inner.

I often add background-color to my DIVs to see how they're laying out on the view. That might be a good way to diagnose what's going onn here.

Answer 3

Unfortunately, all of these solutions rely on specifying a fixed width. Since the tables are generated dynamically (statistical results pulled from a database), the width can not be known in advance.

The desired result can be achieved by wrapping the two tables within another table:

<table align="center"><tr><td>
//code for table on the left
</td><td>
//code for table on the right
</td></tr></table>

and the result is a perfectly centered pair of tables that responds fluidly to arbitrary widths and page (re)sizes (and the align="center" table attribute could be hoisted out into an outer div with margin autos).

I conclude that there are some layouts that can only be achieved with tables.

Answer 4

The problem is that you need to give #inner a set width (anything but auto or inherit). The margin: 0 auto; trick only works if the inner element is narrower than its container element. Without being given a width, #inner is automatically expanding to the full width of #outer, which causes its contents to be flush left.