JavaScript Analog World Clock

This JavaScript code snippet helps you to create an analog world clock. It contains several functions that are responsible for displaying and animating clocks on a webpage. The initInternationalClocks() function initializes the clocks by obtaining the time for different time zones and assigning the degrees of rotation for the clock hands based on that time. It then adds a class to the clock container to show it. The initLocalClocks() function obtains the local time and assigns the degrees of rotation for the clock hands based on that time. The moveSecondHands() function animates the second hand of each clock by incrementing the rotation angle by 6 degrees every second. The setUpMinuteHands() function sets a timeout for the first-minute hand movement and then rotates it every minute after that.

Finally, the moveMinuteHands() function rotates the minute hand of each clock by 6 degrees every minute.

How to Create JavaScript Analog World Clock

Create the HTML structure for the analog world clock as follows:

<div class="demo-container clocks active bounce">
  <article class="clock station js-new-york">
    <section class="label">New York</section>
    <section class="hours-container">
      <section class="hours"></section>
    </section>
    <section class="minutes-container">
      <section class="minutes"></section>
    </section>
    <section class="seconds-container">
      <section class="seconds"></section>
    </section>
  </article>
  <article class="clock station js-london">
    <section class="label">London</section>
    <section class="hours-container">
      <section class="hours"></section>
    </section>
    <section class="minutes-container">
      <section class="minutes"></section>
    </section>
    <section class="seconds-container">
      <section class="seconds"></section>
    </section>
  </article>
  <article class="clock station js-tokyo">
    <section class="label">Tokyo</section>
    <section class="hours-container">
      <section class="hours"></section>
    </section>
    <section class="minutes-container">
      <section class="minutes"></section>
    </section>
    <section class="seconds-container">
      <section class="seconds"></section>
    </section>
  </article>
</div>

Now, style the world clock using the following CSS styles:

body {
  margin: 0;
}

.demo-container.clocks {
  background: #3cd19e;
  padding: 0;
  width: 100%;
  height: 100vh;
  margin: 0;
  overflow: hidden;
}

.clock {
  border-radius: 50%;
  background: radial-gradient(#000, #000 0.1em, #fff 0.1em, #fff), #fff;
  display: inline-block;
  margin: 1%;
  padding-bottom: 31%;
  position: relative;
  top: 50%;
  width: 31%;
  opacity: 0;
  transform: translateY(-40%);
}

.clock.show {
  opacity: 1;
  transform: translateY(-50%);
  transition: all 2.5s 0.5s cubic-bezier(0.12, 1.03, 0.34, 1);
}

.clock::after {
  background: red;
  border-radius: 50%;
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 4%;
  height: 4%;
  z-index: 10;
}

.minutes-container, .hours-container, .seconds-container {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
}

.hours-container {
  -webkit-animation: rotate 43200s infinite linear;
          animation: rotate 43200s infinite linear;
}

.linear .minutes-container {
  -webkit-animation: rotate 3600s infinite linear;
          animation: rotate 3600s infinite linear;
}
.linear .seconds-container {
  -webkit-animation: rotate 60s infinite linear;
          animation: rotate 60s infinite linear;
}

.steps .minutes-container {
  -webkit-animation: rotate 3600s infinite steps(60);
          animation: rotate 3600s infinite steps(60);
}
.steps .seconds-container {
  -webkit-animation: rotate 60s infinite steps(60);
          animation: rotate 60s infinite steps(60);
}

.local.steps .minutes-container {
  -webkit-animation: none;
          animation: none;
}

.bounce .minutes-container {
  transition: transform 0.3s cubic-bezier(0.4, 2.08, 0.55, 0.44);
}
.bounce .seconds-container {
  transition: transform 0.2s cubic-bezier(0.4, 2.08, 0.55, 0.44);
}

.hours {
  background: #000;
  width: 3.5%;
  height: 40%;
  position: absolute;
  left: 48.25%;
  top: 22%;
  transform-origin: 50% 71%;
}

.minutes {
  background: #000;
  width: 3.5%;
  height: 55%;
  position: absolute;
  left: 48.25%;
  top: 7%;
  transform-origin: 50% 78.5%;
}

.seconds {
  background: red;
  width: 1.5%;
  height: 42%;
  position: absolute;
  left: 49.25%;
  top: 20%;
  transform-origin: 50% 71%;
  z-index: 8;
}

.label {
  background: #fff;
  border-radius: 0.25em;
  color: #000;
  font-family: MyriadPro-Regular, "Myriad Pro Regular", MyriadPro, "Myriad Pro", Helvetica, Arial, sans-serif;
  font-size: 1em;
  font-weight: bold;
  text-transform: uppercase;
  padding: 0.5em 0.75em 0.25em;
  position: absolute;
  top: -4em;
  left: 50%;
  transform: translate(-50%, 0);
}

@-webkit-keyframes rotate {
  100% {
    transform: rotateZ(360deg);
  }
}

@keyframes rotate {
  100% {
    transform: rotateZ(360deg);
  }
}
.clock.station {
  background: #fff url(//cssanimation.rocks/assets/images/posts/clocks/station_clock.svg) no-repeat center;
  background-size: 95%;
  box-shadow: 0 0 0.5em rgba(0, 0, 0, 0.2) inset;
}

.clock.station .seconds::before {
  background: red;
  border-radius: 50%;
  content: "";
  position: absolute;
  top: -9%;
  left: -200%;
  height: 18%;
  width: 500%;
}

.clock.ios7 {
  background: #fff url(/assets/images/posts/clocks/ios_clock.svg) no-repeat center;
  background-size: 88%;
}

.clock.ios7:before {
  background: black;
  border-radius: 50%;
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 6%;
  height: 6%;
  z-index: 0;
}

.clock.ios7:after {
  width: 2%;
  height: 2%;
}

.clock.ios7 .seconds {
  border-radius: 200%/10%;
  height: 30%;
  left: 49.5%;
  top: 20%;
  width: 1%;
  transform-origin: 50% 100%;
}

.clock.ios7 .minutes {
  border-radius: 150%/10%;
  width: 2%;
  height: 35%;
  left: 49%;
  top: 15%;
  transform-origin: 50% 100%;
}

.clock.ios7 .hours {
  border-radius: 85%/10%;
  width: 2%;
  height: 20%;
  left: 49%;
  top: 30%;
  transform-origin: 50% 100%;
}

.clock.simple {
  background: #fff url(/assets/images/posts/clocks/ios_clock.svg) no-repeat center;
  background-size: 88%;
}

.clock.simple:after {
  background-color: #000;
  width: 5%;
  height: 5%;
}

.clock.simple .seconds {
  background-color: #000;
  height: 45%;
  left: 49.5%;
  top: 14%;
  width: 1%;
  transform-origin: 50% 80%;
}

.clock.simple .minutes {
  width: 2%;
  height: 40%;
  left: 49%;
  top: 10%;
  transform-origin: 50% 100%;
}

.clock.simple .hours {
  width: 2.5%;
  height: 20%;
  left: 48.75%;
  top: 30%;
  transform-origin: 50% 100%;
}

.hours.angled {
  transform: rotateZ(-40deg);
}

.minutes.angled {
  transform: rotateZ(40deg);
}

Load the following scripts before closing the body tag:

<script src='https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.9.0/moment.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.9.0/locales.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/moment-timezone/0.3.0/moment-timezone.min.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/moment-timezone/0.3.0/moment-timezone-utils.min.js'></script>

Finally, add the following JavaScript function for its functionality:

/*
 *  Main function to set the clock times
 */
(function() {
  // Initialise the locale-enabled clocks
  initInternationalClocks();
  // Initialise any local time clocks
  initLocalClocks();
  // Start the seconds container moving
  moveSecondHands();
  // Set the intial minute hand container transition, and then each subsequent step
  setUpMinuteHands();
})();

/*
 *  Set up an entry for each locale of clock we want to use
 */
 function getTimes() {
  moment.tz.add([
    'Eire|GMT IST|0 -10|01010101010101010101010|1BWp0 1qM0 WM0 1qM0 WM0 1qM0 11A0 1o00 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 WM0 1qM0 11A0 1o00 11A0 1o00',
    'Asia/Tokyo|JST|-90|0|',
    'America/New_York|EST EDT|50 40|0101|1Lz50 1zb0 Op0'
    ]);
  var now = new Date();
  // Set the time manually for each of the clock types we're using
  var times = [
    {
      jsclass: 'js-tokyo',
      jstime: moment.tz(now, "Asia/Tokyo")
    },
    {
      jsclass: 'js-london',
      jstime: moment.tz(now, "Eire")
    },
    {
      jsclass: 'js-new-york',
      jstime: moment.tz(now, "America/New_York")
    }
  ];
  return times;
}

/*
 * Set up the clocks that use moment.js
 */
function initInternationalClocks() {
  // Initialise the clock settings and the three times
  var times = getTimes();
  for (i = 0; i < times.length; ++i) {
    var hours = times[i].jstime.format('h');
    var minutes = times[i].jstime.format('mm');
    var seconds = times[i].jstime.format('ss');

    var degrees = [
      {
        hand: 'hours',
        degree: (hours * 30) + (minutes / 2)
      },
      {
        hand: 'minutes',
        degree: (minutes * 6)
      },
      {
        hand: 'seconds',
        degree: (seconds * 6)
      }
    ];
    for (var j = 0; j < degrees.length; j++) {
      var elements = document.querySelectorAll('.active .' + times[i].jsclass + ' .' + degrees[j].hand);
      for (var k = 0; k < elements.length; k++) {
        	elements[k].style.webkitTransform = 'rotateZ('+ degrees[j].degree +'deg)';
          elements[k].style.transform = 'rotateZ('+ degrees[j].degree +'deg)';
          // If this is a minute hand, note the seconds position (to calculate minute position later)
          if (degrees[j].hand === 'minutes') {
            elements[k].parentNode.setAttribute('data-second-angle', degrees[j + 1].degree);
          }
      }
    }
  }
  // Add a class to the clock container to show it
  var elements = document.querySelectorAll('.clock');
  for (var l = 0; l < elements.length; l++) {
    elements[l].className = elements[l].className + ' show';
  }
}

/*
 * Starts any clocks using the user's local time
 */
function initLocalClocks() {
  // Get the local time using JS
  var date = new Date;
  var seconds = date.getSeconds();
  var minutes = date.getMinutes();
  var hours = date.getHours();

  // Create an object with each hand and it's angle in degrees
  var hands = [
    {
      hand: 'hours',
      angle: (hours * 30) + (minutes / 2)
    },
    {
      hand: 'minutes',
      angle: (minutes * 6)
    },
    {
      hand: 'seconds',
      angle: (seconds * 6)
    }
  ];
  // Loop through each of these hands to set their angle
  for (var j = 0; j < hands.length; j++) {
    var elements = document.querySelectorAll('.local .' + hands[j].hand);
    for (var k = 0; k < elements.length; k++) {
        elements[k].style.transform = 'rotateZ('+ hands[j].angle +'deg)';
        // If this is a minute hand, note the seconds position (to calculate minute position later)
        if (hands[j].hand === 'minutes') {
          elements[k].parentNode.setAttribute('data-second-angle', hands[j + 1].angle);
        }
    }
  }
}

/*
 * Move the second containers
 */
function moveSecondHands() {
  var containers = document.querySelectorAll('.bounce .seconds-container');
  setInterval(function() {
    for (var i = 0; i < containers.length; i++) {
      if (containers[i].angle === undefined) {
        containers[i].angle = 6;
      } else {
        containers[i].angle += 6;
      }
      containers[i].style.webkitTransform = 'rotateZ('+ containers[i].angle +'deg)';
      containers[i].style.transform = 'rotateZ('+ containers[i].angle +'deg)';
    }
  }, 1000);
  for (var i = 0; i < containers.length; i++) {
    // Add in a little delay to make them feel more natural
    var randomOffset = Math.floor(Math.random() * (100 - 10 + 1)) + 10;
    containers[i].style.transitionDelay = '0.0'+ randomOffset +'s';
  }
}

/*
 * Set a timeout for the first minute hand movement (less than 1 minute), then rotate it every minute after that
 */
function setUpMinuteHands() {
  // More tricky, this needs to move the minute hand when the second hand hits zero
  var containers = document.querySelectorAll('.minutes-container');
  var secondAngle = containers[containers.length - 1].getAttribute('data-second-angle');
  console.log(secondAngle);
  if (secondAngle > 0) {
    // Set a timeout until the end of the current minute, to move the hand
    var delay = (((360 - secondAngle) / 6) + 0.1) * 1000;
    console.log(delay);
    setTimeout(function() {
      moveMinuteHands(containers);
    }, delay);
  }
}

/*
 * Do the first minute's rotation, then move every 60 seconds after
 */
function moveMinuteHands(containers) {
  for (var i = 0; i < containers.length; i++) {
    containers[i].style.webkitTransform = 'rotateZ(6deg)';
    containers[i].style.transform = 'rotateZ(6deg)';
  }
  // Then continue with a 60 second interval
  setInterval(function() {
    for (var i = 0; i < containers.length; i++) {
      if (containers[i].angle === undefined) {
        containers[i].angle = 12;
      } else {
        containers[i].angle += 6;
      }
      containers[i].style.webkitTransform = 'rotateZ('+ containers[i].angle +'deg)';
      containers[i].style.transform = 'rotateZ('+ containers[i].angle +'deg)';
    }
  }, 60000);
}

That’s all! hopefully, you have successfully created JavaScript analog world clock. If you have any questions or suggestions, feel free to comment below.