Create Digital Alarm Clock With Ringtone & Custom Icons in JavaScript HTML5 CSS3

In this tutorial, I will teach you how to create a Digital Alarm Clock with Ringtone using HTML5, CSS3, and JavaScript. The complete source code of this JavaScript alarm clock app is given below.

You can download the full source code (including images and ringtone) of this JavaScript alarm clock app at the end of this article.

JavaScript Alarm Clock App Source Code

index.html

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title>Alarm Clock in JavaScript</title>
    <link rel="stylesheet" href="style.css">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
  </head>
  <body>
    <div class="wrapper">
      <img src="./files/clock.svg" alt="clock">
      <h1>00:00:00 PM</h1>
      <div class="content">
        <div class="column">
          <select>
            <option value="Hour" selected disabled hidden>Hour</option>
          </select>
        </div>
        <div class="column">
          <select>
            <option value="Minute" selected disabled hidden>Minute</option>
          </select>
        </div>
        <div class="column">
          <select>
            <option value="AM/PM" selected disabled hidden>AM/PM</option>
          </select>
        </div>
      </div>
      <button>Set Alarm</button>
    </div>

    <script src="script.js"></script>

  </body>
</html>

script.js

const currentTime = document.querySelector("h1"),
content = document.querySelector(".content"),
selectMenu = document.querySelectorAll("select"),
setAlarmBtn = document.querySelector("button");

let alarmTime, isAlarmSet,
ringtone = new Audio("./files/ringtone.mp3");

for (let i = 12; i > 0; i--) {
    i = i < 10 ? `0${i}` : i;
    let option = `<option value="${i}">${i}</option>`;
    selectMenu[0].firstElementChild.insertAdjacentHTML("afterend", option);
}

for (let i = 59; i >= 0; i--) {
    i = i < 10 ? `0${i}` : i;
    let option = `<option value="${i}">${i}</option>`;
    selectMenu[1].firstElementChild.insertAdjacentHTML("afterend", option);
}

for (let i = 2; i > 0; i--) {
    let ampm = i == 1 ? "AM" : "PM";
    let option = `<option value="${ampm}">${ampm}</option>`;
    selectMenu[2].firstElementChild.insertAdjacentHTML("afterend", option);
}

setInterval(() => {
    let date = new Date(),
    h = date.getHours(),
    m = date.getMinutes(),
    s = date.getSeconds(),
    ampm = "AM";
    if(h >= 12) {
        h = h - 12;
        ampm = "PM";
    }
    h = h == 0 ? h = 12 : h;
    h = h < 10 ? "0" + h : h;
    m = m < 10 ? "0" + m : m;
    s = s < 10 ? "0" + s : s;
    currentTime.innerText = `${h}:${m}:${s} ${ampm}`;

    if (alarmTime === `${h}:${m} ${ampm}`) {
        ringtone.play();
        ringtone.loop = true;
    }
});

function setAlarm() {
    if (isAlarmSet) {
        alarmTime = "";
        ringtone.pause();
        content.classList.remove("disable");
        setAlarmBtn.innerText = "Set Alarm";
        return isAlarmSet = false;
    }

    let time = `${selectMenu[0].value}:${selectMenu[1].value} ${selectMenu[2].value}`;
    if (time.includes("Hour") || time.includes("Minute") || time.includes("AM/PM")) {
        return alert("Please, select a valid time to set Alarm!");
    }
    alarmTime = time;
    isAlarmSet = true;
    content.classList.add("disable");
    setAlarmBtn.innerText = "Clear Alarm";
}

setAlarmBtn.addEventListener("click", setAlarm);

style.css

/* Import Google font - Poppins */@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600&display=swap');
*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
}
body, .wrapper, .content{
  display: flex;
  align-items: center;
  justify-content: center;
}
body{
  padding: 0 10px;
  min-height: 100vh;
  background: #4A98F7;
}
.wrapper{
  width: 440px;
  padding: 30px 30px 38px;
  background: #fff;
  border-radius: 10px;
  flex-direction: column;
  box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}
.wrapper img{
  max-width: 103px;
}
.wrapper h1{
  font-size: 38px;
  font-weight: 500;
  margin: 30px 0;
}
.wrapper .content{
  width: 100%;
  justify-content: space-between;
}
.content.disable{
  cursor: no-drop;
}
.content .column{
  padding: 0 10px;
  border-radius: 5px;
  border: 1px solid #bfbfbf;
  width: calc(100% / 3 - 5px);
}
.content.disable .column{
  opacity: 0.6;
  pointer-events: none;
}
.column select{
  width: 100%;
  height: 53px;
  border: none;
  outline: none;
  background: none;
  font-size: 19px;
}
.wrapper button{
  width: 100%;
  border: none;
  outline: none;
  color: #fff;
  cursor: pointer;
  font-size: 20px;
  padding: 17px 0;
  margin-top: 20px;
  border-radius: 5px;
  background: #4A98F7;
}

Download Source Code (including images and ringtone)

Download

Furqan

Well. I've been working for the past three years as a web designer and developer. I have successfully created websites for small to medium sized companies as part of my freelance career. During that time I've also completed my bachelor's in Information Technology.

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