Countdown Timer and Date Calculator for Deadlines
Count down to any deadline or event. Calculate days between dates, including business days. Live countdown with shareable link.
The problem
"How many days until the launch?" is a surprisingly annoying question to answer. You pull up a calendar and start counting, second-guessing whether you included the end date. Worse, if someone asks "how many business days," you're now mentally skipping weekends and holidays. And if you want a live countdown for a team — say, days until a product release or a conference — there's no quick way to share one without signing up for yet another app.
How it works
- Pick a target date — type it in or use the date picker.
- See the countdown — days, hours, minutes, and seconds update in real time.
- Calculate between dates — enter two dates to see the difference in calendar days and business days.
- Share it — the URL updates with your target date, so you can send the link to anyone and they'll see the same countdown.
Everything runs in your browser. No account, no server, no data stored anywhere.
When to use this tool
Tracking a project deadline. Counting down to a product launch, conference, or vacation. Figuring out how many business days you have to deliver something. Sharing a countdown link with your team in Slack. Calculating how many days are between two dates for an invoice, a contract term, or a project plan.
Why I built it
I needed to answer "how many working days until X" for project planning, and I was tired of counting on a calendar. The shareable URL feature came from wanting to drop a countdown link into a team chat so everyone could see the same number without me recalculating it every morning.
Tips and reference
When estimating project timelines, business days matter more than calendar days. A two-week deadline sounds like 14 days but is really only 10 working days — and less if there's a holiday in between. Always double-check whether a deadline means "by end of day on that date" or "before that date starts." It's a common source of off-by-one confusion in project planning.
Built with vanilla HTML/JS. No frameworks, no backend, loads instantly.