JSFiddle - React, Tailwind, and code Playground
HTML
<progress id="progressBar" value="0.5" max="1"></progress>
<div id="result"></div>
CSS
#progressBar {
width:300px;
}
JavaScript
document.getElementById('progressBar').addEventListener('click', function (e) {
var x = e.pageX - this.offsetLeft;
//Uncomment the following line to activate alert
//alert('Current position: ' + document.getElementById('progressBar').position);
//Save position before the click
var startPos = document.getElementById('progressBar').position;
//Convert x value to progress range [0 1]
var xconvert = x/300; //cause width is 300px and you need a value in [0,1] range
var finalx = (xconvert).toFixed(1); //round up to one digit after coma
//Uncomment the following line to activate alert
//alert('Click value: ' + finalx);
//If you don't want change progress bar value after click comment the following line
document.getElementById('progressBar').value = finalx;
document.getElementById('result').innerHTML = ('Start position: ' + startPos + "<br/><br/>");
document.getElementById('result').innerHTML += ('Current position: ' + document.getElementById('progressBar').position + "<br/>");
document.getElementById('result').innerHTML += ('Current value: ' + document.getElementById('progressBar').value + "<br/></br/>");
document.getElementById('result').innerHTML += ('Real click value: ' + xconvert + "<br/>");
document.getElementById('result').innerHTML += ('Current value set in progressbar: ' + finalx + "<br/>");
});