JavaScript Convert 12 Hour AM/PM Time to 24 Hour Time Format

We’ll show you how to use JavaScript to convert a 12 hour format to a 24 hour format today. We’ll demonstrate how to convert using a custom function and the Moment.js function.

There are a few more articles on DateTime and Time Zone on this page.

Convert a 12 hour format to 24 hour format

1. Using Moment.js
2. Using custom function

1. Using Moment.js

To use the moment functions, you must include the following moment script.

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.26.0/moment.min.js"></script>

To retrieve the converted time, use the JavaScript code below.

var convertedTime = moment("01:00 PM", 'hh:mm A').format('HH:mm')
console.log(convertedTime);
// Output: 13:00

2. Using custom function

We’ll use the following custom JavaScript function to convert the 12 hour format to 24 hour format in this second method.

const convertTime12to24 = time12h => {
  const [time, modifier] = time12h.split(" ");

  let [hours, minutes] = time.split(":");

  if (hours === "12") {
    hours = "00";
  }

  if (modifier === "PM") {
    hours = parseInt(hours, 10) + 12;
  }

  return `${hours}:${minutes}`;
};

var convertedTime = convertTime12to24("01:00 PM");
console.log(convertedTime);
// Output: 13:00

I hope you find this article helpful.
Thank you for reading. Happy Coding..!!