first-input-delay/demo/index.html

A JavaScript library for measuring the First Input Delay metric. See https://goo.gl/1AKcj5.

<script src="../dist/first-input-delay.min.js"></script>

<script>
perfMetrics.onFirstInputDelay(function(delay, evt) {
  console.log('First Input Delay', delay);
  console.log('Event details', evt);
});
</script>