How is “days until” calculated?

The big number is the difference in calendar days between today and the target date, regardless of the current time — the same way calendar and countdown apps count. The ticker underneath shows the exact time left to the second (to midnight at the start of the target day if no time is set), so in the afternoon the two can differ by one, which is expected.

Does “days since” include the first day?

By default it’s the plain difference: if you started yesterday, today shows 1 day. Many people prefer to count the first day as “Day 1” — tick the option under the list to add one and show “Day N” instead.

How do I set up birthdays and yearly anniversaries?

Enter the original date (the birth date or wedding date) and set Repeat to “Every year”. The tool counts down to the next occurrence this year or next, shows which anniversary it will be, and how many days have passed since the original date. Feb 29 birthdays use Feb 28 in non-leap years.

Where are events stored, and does sharing expose the others?

Events are stored only in your browser’s local storage and never uploaded. A share link encodes just the one event — title, date, time, icon, color and repeat — after the # in the URL, not the rest of your list. The person opening it can save it to their own list.

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⏳Days Until & Days Since Counter - Countdown to Any Date, Anniversaries & Birthdays

Keep every important date in view: how many days until the exam, the holiday or the trip, how many days you’ve been together, how old the baby is in days. Each event has a date with an optional time, an icon and a color. Pick one and it shows a big “days until” or “days since” number, with a live days-hours-minutes-seconds readout below. Birthdays, wedding anniversaries and holidays can repeat every year, so the tool finds the next occurrence and shows which anniversary it is along with the total days since the original date; monthly repeats work too. Full-screen mode is perfect for a spare monitor or a projector, and “Copy share link” creates a link to just that one event — friends see a clean countdown page and can save it to their own list. This tool counts calendar days; for short minute-and-second countdowns, a stopwatch or Pomodoro sessions, use the Online Timer.

Free · No sign-up · Runs in your browserLast updated: 2026-10-26

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How to use Days Until / Days Since

1Click “New event” and set a title, date (time optional), icon and color
2Choose “Every year” for birthdays and anniversaries; future dates count down, past dates count up
3Pick events from the list, go full screen or copy a share link

FAQ

How is “days until” calculated?: The big number is the difference in calendar days between today and the target date, regardless of the current time — the same way calendar and countdown apps count. The ticker underneath shows the exact time left to the second (to midnight at the start of the target day if no time is set), so in the afternoon the two can differ by one, which is expected.
Does “days since” include the first day?: By default it’s the plain difference: if you started yesterday, today shows 1 day. Many people prefer to count the first day as “Day 1” — tick the option under the list to add one and show “Day N” instead.
How do I set up birthdays and yearly anniversaries?: Enter the original date (the birth date or wedding date) and set Repeat to “Every year”. The tool counts down to the next occurrence this year or next, shows which anniversary it will be, and how many days have passed since the original date. Feb 29 birthdays use Feb 28 in non-leap years.
Where are events stored, and does sharing expose the others?: Events are stored only in your browser’s local storage and never uploaded. A share link encodes just the one event — title, date, time, icon, color and repeat — after the # in the URL, not the rest of your list. The person opening it can save it to their own list.