zzz Countdown Calendar: Check Exact Time,Date and plan.

Today, I wanted to make a simple countdown timer, you know, like for New Year’s or something. I’ve named it “zzz countdown” ’cause, well, it’s kinda basic, and I was feeling sleepy.

First, I fired up my code editor. Nothing fancy, just a plain HTML file to start. I needed a place to show the countdown, so I threw in a div with an ID. I figured I’d grab that later with JavaScript.

Setting up the HTML

My HTML was pretty barebones:

<div id="countdown"></div>

Yep, that’s it. Just one div. All the magic was gonna happen in the script.

The JavaScript Part

Okay, so now for the JavaScript. First thing, I needed to get today’s date and the target date (like New Year’s). I used the Date object for that. It’s built-in, so, super convenient.

let today = new Date();
let targetDate = new Date('January 1, 2025 00:00:00');

I hardcoded the target date for now. I’ll probably make that adjustable later, maybe with an input field or something.

Next up, I needed to calculate the difference between those two dates. I got the time in milliseconds for both, subtracted them, and then did some math to get days, hours, minutes, and seconds.

let timeDiff = *() - *();
let days = *(timeDiff / (1000  60  60  24));
let hours = *((timeDiff % (1000  60  60  24)) / (1000  60  60));
let minutes = *((timeDiff % (1000  60  60)) / (1000  60));
let seconds = *((timeDiff % (1000  60)) / 1000);

Lots of dividing and remainders there. The thing just chops off the decimals, giving me whole numbers.

Making it Tick

I wanted the countdown to update every second, right? So, I used setInterval(). It’s a function that runs another function repeatedly after a set amount of time. I set it to 1000 milliseconds, which is one second.

setInterval(updateCountdown, 1000);

updateCountdown is my function to re-calculate and to show the time.

Inside the updateCountdown function, I basically did all that date math again, and then I updated the HTML of that div I mentioned earlier.

• Grab the countdown div:*(‘countdown’)
• Set it is innerHTML:* = …

function updateCountdown() {
let today = new Date();
let timeDiff = *() - *();
//Do the math same with above...

let countdownElement = *('countdown');
* = days + "d " + hours + "h "
+ minutes + "m " + seconds + "s ";

I just mashed together the days, hours, minutes, and seconds with some letters to make it readable. Put “d”, “h”, “m”,”s” behind them.

And… that’s pretty much it! I saved the file, opened it in my browser, and boom, a working countdown timer. It’s not the prettiest thing, but it works! I might add some styling later, maybe some animations, but for now, I’m happy with my little “zzz countdown”. It was a fun little project to kill some time.