JSFiddle - React, Tailwind, and code Playground

by molecule

JavaScript

var timestamp1 = Date.UTC(2011, 7, 20, 1, 13);
var d = new Date();
var timestampNow = Date.UTC(d.getUTCFullYear(), d.getUTCMonth(), d.getUTCDay(), d.getUTCHours(), d.getUTCMinutes(), d.getUTCMilliseconds());

var seconds = Math.abs(Math.round((timestampNow - timestamp1)/1000));
var minutes = Math.floor(seconds / 60);
var leftSeconds = seconds % 60;
var hours = Math.floor(minutes / 60);
var leftMinutes = minutes % 60;
var days = Math.floor(hours / 24);
var leftHours = hours % 24;
var years = Math.floor(days / 365);
var leftDays = hours % 365;

var result = '';
if (timestampNow > timestamp1)
    result += 'Started ';
else
    result += 'Will start in ';
if (years)
    result += years + ' years ';
if (leftDays)
    result += leftDays + ' days ';
if (leftHours)
    result += leftHours + ' hrs ';
if (leftMinutes)
    result += leftMinutes + ' mins ';
if (leftSeconds)
    result += leftSeconds + ' secs ';

alert(result);