import { animate, utils } from 'animejs';

animate('input', {
  value: 1000, // animate the input "value" attribute
  alternate: true,
  loop: true,
  modifier: utils.round(0),
});

<pre class="row large centered">
  <input type="range" value="0" min="0" max="1000" />
  <input type="text" value="0" size="5"/>
</pre>