Creating a clock using JavaScript

Imagine a clock that shows the time to your users, on a travel site for example, with the time zone of the destination country? Let's create this magnificent clock together, using JavaScript!

Louis-Nicolas Leuillet

Updated on December 9, 2024

Imagine a clock that shows the time to your users, for example on a travel website with the destination country's time zone? Let’s create this magnificent clock together easily with JavaScript!

Step 1

Let's start with the HTML code.

HTML

<div class="clock">
  <div class="wrap">
    <span class="heure"></span>
    <span class="minute"></span>
    <span class="seconde"></span>
    <span class="dot"></span>
  </div>
</div>

.clock defines the clock, .wrap defines the background of the clock, .heure, .minute, .seconde are the hands, and .dot represents the central circle that unites the hands.

Step 2

Let's style the clock and its background.

CSS

.clock {
	 border-radius: 50%;
	 background: #fff;
	 border: 5px solid white;
	 box-shadow: inset 2px 3px 8px 0 rgba(0, 0, 0, 0.1);
}

.wrap {
	 position: relative;
	 width: 350px;
	 height: 350px;
}

Step 3

Let's move on to the hands.

CSS

.minute, .heure {
	 position: absolute;
	 height: 100px; width: 6px;
	 margin: auto;
	 top: -27%; left: 0;	bottom: 0; right: 0;
	 transform-origin: bottom center;
	 transform: rotate(0deg);
	 box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.4);
     background: black;
}

Step 4

Let's refine the minute hand.

CSS

.minute {
	 position: absolute;
	 height: 130px;
	 width: 4px;
	 top: -38%;
	 left: 0;
	 box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.4);
	 transform: rotate(90deg);
}

After styling the minute and hour hands, we will now style the minute hand more precisely to differentiate them.

Step 5

Let's move on to the second hand.

CSS

.seconde {
	 position: absolute;
	 height: 90px;
	 width: 2px;
	 margin: auto;
	 top: -26%;
	 left: 0;
	 bottom: 0;
	 right: 0;
	 border-radius: 4px;
	 background: #ff4b3e;
	 transform-origin: bottom center;
	 transform: rotate(180deg);
}

We will style and make the second hand red.

Step 6

Let's handle the central circle.

CSS

.dot {
	 position: absolute;
	 top: 0;
	 left: 0;
	 right: 0;
	 bottom: 0;
	 width: 12px;
	 height: 12px;
	 border-radius: 50%;
	 background: white;
	 border: 2px solid #1b1b1b;
	 border-radius: 50%;
	 margin: auto;
}

This central circle will serve to unite all the hands at a single point.

Step 7

Let's finish with JavaScript to make our clock functional.

JAVASCRIPT

clock();

function clock() {
  const date = new Date();
  const hours = ((date.getHours() + 11) % 12 + 1);
  const minutes = date.getMinutes();
  const seconds = date.getSeconds();
  const hour = hours * 30;
  const minute = minutes * 6;
  const second = seconds * 6;
  
  document.querySelector('.heure').style.transform = `rotate(${hour}deg)`;

  document.querySelector('.minute').style.transform = `rotate(${minute}deg)`;

  document.querySelector('.seconde').style.transform = `rotate(${second}deg)`;
}

setInterval(clock, 1000);

Category: Development