JSFiddle - React, Tailwind, and code Playground

HTML

<div id="likes">500</div>
<div id="dislikes">50</div>
<meter value="10" min="0" max="1000" id="somemeter"></meter>

JavaScript

(function() {
  var meter = document.getElementById('somemeter');
  var Likes = document.getElementById('likes');
  var Dislikes = document.getElementById('dislikes');

  meter.max = Likes.innerHTML + Dislikes.innerHTML;
  meter.value = Likes.innerHTML - Dislikes.innerHTML;
})();