How to use this timer
Enter hours, minutes, and seconds (or use presets), then tap Start countdown. When time hits zero you get a sound and an optional browser notification.
Timer vs days-until
For days until a calendar date, use the days-until calculator. This page is for fixed-duration timers—breaks, cooking, focus sessions.
Share a duration
Duration fields sync to the URL—Copy link shares the same defaults (each person still taps Start).
Frequently asked questions
Countdown timer vs days-until?
This page is a duration timer—set hours/minutes/seconds and get a sound plus notification when time is up. For calendar days between two dates, use the days-until calculator.
How do I get alerted when time is up?
You hear a sound and see a “time’s up” message on the page. Allow notifications for alerts when the tab is in the background. Keep this page open while the timer runs.
What if the target date is in the past?
The tool shows how many days since the date passed—positive days—instead of confusing negative numbers.
Is the years/months/days breakdown exact?
The breakdown walks the calendar month-by-month (not “days ÷ 365”); total days still match the calendar span between the two dates.
Different from the date difference calculator?
The date difference tool compares any start/end pair; this page is tuned for event countdowns (often today → target).
Do leap years affect the countdown?
Yes—totals use real calendar days including Feb 29 in leap years. Check a year with the leap year calculator.
Can I save my inputs?
Yes. Copy link below the form keeps your current inputs so you can share the scenario or save it for later.
More date calculators?
Browse the date & time hub for add/subtract days, business days, weekday lookup, and more.