Birthday calculator — your next birthday, counted down
A birthday calculator answers three questions at once: how old you are now, when your next birthday falls, and exactly how many days until it. Enter your date of birth below and get all three — plus the weekday of your next birthday and the age you will turn.
🔒 100% private: the dates you enter never leave your device. All calculations happen in your browser — nothing is uploaded, stored, or seen by us.
Planning around a birthday
Knowing the day count, not just the month, is what makes planning easy: booking a party venue, ordering a cake, sending invitations, or counting down with children. The calculator gives you the exact number of days, so "about three months away" becomes "96 days away, on a Saturday, when you turn 34".
What counts as your birthday in a leap year
If you were born on 29 February, your birthday is observed on 1 March in non-leap years — that is the convention this calculator uses when working out your next birthday and the age you turn. Our guide to how to calculate age explains the leap-year handling in full.
More than the countdown
The same result also gives your exact current age in years, months and days, your total days lived, and the weekday you were born on — everything a birthday question usually leads to. If you want your age on a different date instead, set the "Age at date" field and the calculator re-works the whole result for that day.
Frequently asked questions
When is my birthday?
Enter your date of birth above and the calculator shows your next birthday's date and weekday, plus how many days away it is.
How many days are there until my next birthday?
The results count the exact days from today to your next birthday, using the real calendar.
What age will I turn on my next birthday?
The next-birthday line states the age you will turn, alongside the date and weekday.
What does an age calculator on birthday mean?
It means a calculator that starts from your birthday — your date of birth — and works out your age and your next birthday from it. That is exactly what this page does.
I was born on 29 February. When is my birthday in other years?
In non-leap years your birthday is observed on 1 March, and the calculator uses that date for your next birthday and the age you turn.
Is my date of birth private?
Completely. The calculator runs in your browser; the dates you enter are never uploaded or stored anywhere.
Looking for the general calculator? It is on the AgeCalc home page →