JSFiddle - React, Tailwind, and code Playground

by Tan

HTML

<p><span id="value1">0</span>%</p>

<p>£<span id="value2">0</span></p>

JavaScript

function commaSeparateNumber(val) {
    while (/(\d+)(\d{3})/.test(val.toString())) {
        val = val.toString().replace(/(\d)(?=(\d\d\d)+(?!\d))/g, "$1,");
    }
    return val;
}

function animateValue(id, start, end, duration) {
    var range = end - start;
    var current = start;
    var increment = end > start? 1 : -1;
    var stepTime = Math.abs(Math.floor(duration / range));
    var obj = document.getElementById(id);
    var timer = setInterval(function() {
        current += increment;
        obj.innerHTML = current;
        if (current == end) {
            clearInterval(timer);
        }
    }, stepTime);
}

animateValue("value1", 0, 79, 1000);

animateValue("value2", 0, 800, 1);