UnitConv

Countdown Calculator

Count how many days are left until an event, anniversary, birthday or holiday. Supports any date, yearly anniversaries and the next holiday.

Please enter a valid date.

Related calculators

Business Days CalculatorWeek Number CalculatorDay of the Week CalculatorDate Difference Calculator

What is the Countdown Calculator?

The Countdown Calculator instantly tells you how many days are left until a target day. It has three modes. "Until a date" counts the days remaining until any date such as a trip, exam, deadline or due date. "Yearly anniversary" handles days that recur on the same month and day every year, like a birthday or wedding anniversary, returning the next occurrence this year or next. "Next holiday" lists the upcoming public holidays for the country you select. Beyond the day count, it also shows a years/months/days and weeks breakdown plus the weekday, and you can share the result in one tap.

How to use it

1. Pick a mode: "Until a date", "Yearly anniversary" or "Next holiday". 2. For "Until a date", just choose your target date and the remaining (or elapsed) days appear instantly. 3. For "Yearly anniversary", enter an optional event name plus the month and day. If this year's date has already passed, next year's occurrence is calculated automatically. 4. For "Next holiday", choose a country (Japan or the United States) to see the nearest holidays listed with a "days to go" count. 5. Tap "Share" to post your countdown to social media or messaging apps.

How it works

Days remaining = the whole-day difference between the target date and today, both measured at midnight UTC. Using UTC avoids time-zone drift. The years/months/days breakdown is a calendar-based difference (handling leap years and month-end clamping), and the weeks breakdown is the total days divided by 7 with a remainder. For a yearly anniversary, the calculator returns this year's date if it is still upcoming, otherwise the first occurrence in a later year. Because February 29 only exists in leap years, it advances to the next real February 29 in an actual leap year.

Frequently asked questions

How is "days to go" counted? ▾

It computes the whole-day difference between the target date and today, measured at midnight UTC. Tomorrow shows "1 day to go", the day after "2 days to go", and so on. Because the count uses UTC, you get the same result anywhere in the world.

What happens if my anniversary is February 29 (leap day)? ▾

February 29 only exists in a leap year, which happens once every four years. This tool does not round it to February 28 or March 1; instead it counts down to the next February 29 that actually exists, and shows a note that it falls on the next leap year.

Which countries are supported for the next holiday? ▾

Japan and the United States are currently supported. Japan includes substitute holidays, citizens' holidays and the vernal/autumnal equinox, while the US covers federal holidays. Both are computed from the year automatically, so they are always up to date. The next five holidays are shown with a "days to go" count.

What can I use it for? ▾

Use it for trips, exams, deadlines, due dates, payday, or the countdown to your favorite concert. It is also handy for tracking yearly birthdays and wedding anniversaries, or checking the next long weekend or public holiday. The share feature makes it easy to get family and friends excited too.

What happens if I enter a past date? ▾

If you enter a past date, it shows the days elapsed since then (for example "100 days ago"). In anniversary mode, even if this year's date has passed, next year's occurrence is calculated automatically, so a future countdown is always shown.

This tool provides general day calculations and estimates. Holidays are computed automatically for the supported years (1980-2099) in Japan and the US and do not include ad-hoc holidays or company- or region-specific closures. Always confirm important dates with official sources.