JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.0/jquery.min.js"></script>
<div id="myDiv">
  <table>
    <tr>
      <th>title 1</th>
      <td>para 1-1</td>
    </tr>
  </table>
  <table>
    <tr>
      <th>title 2</th>
      <td>para 2-1</td>
      <td>para 2-2</td>
      <td>para 2-3</td>
    </tr>
  </table>
  <table>
    <tr>
      <th>title 3</th>
      <td>para 3-1</td>
      <td>para 3-2</td>
    </tr>
  </table>
</div>

<br>
<pre>
 <div id="jsonOut">
 
 </div> 
</pre>

JavaScript

$(document).ready(function() {
  myHTML = $('#myDiv').html();
});

var tableNumber = $('#myDiv').children('table').length;

var items = [];

for (i = 0; i < tableNumber; i++) {
  var title = $($("table tr th")[i]).html();

var paras = [];

  $($("table tr")[i]).find('td').each(function() {
    paras.push($(this).html());
  }); 
	items.push(title,paras);
}

var outPut = JSON.stringify(items);

$('#jsonOut').html(outPut);