DefinitelyTyped/types/countup.js/countup.js-tests.ts

const b = new CountUp(".foo", 0, 100);

const options: CountUp.CountUpOptions = {
    decimal: ",",
    useGrouping: true,
    suffix: "-",
    prefix: "=",
    separator: "/",
    useEasing: true,
    formattingFn: number => number + "-",
    easingFn: (t, b, c, d) => t + b + c + d,
    numerals: ["q", 2, "e", [3], "t", 0, "u", 7, "o", "p"]
};

const element = document.getElementById("#id");
if (element) {
    const instance2 = new CountUp(element, 2, "3", 0, "5", options);
}

const instance = new CountUp(".js-target", 2, "3", 0, "5", options);

instance.start();

instance.start(() => {
    console.log(instance.version());
});

instance.update(999);

instance.pauseResume();

if (instance.paused) instance.reset();