Your birthday is processed in your browser and is not stored. Birth year is optional and is only used to show the age you will turn.
Happy Birthday! Your birthday is today.
Your Upcoming Birthdays
| Birthday | Date | Weekday | Age You’ll Turn |
|---|
How the Birthday Calculator Works
Your birthday repeats on the same month and day each year. To find your next birthday, the calculator first checks that date in the current calendar year.
- If your birthday is still ahead this year, that date is used as your next birthday.
- If your birthday has already passed, the same month and day in the following year becomes your next birthday.
- If today is your birthday, the calculator shows 0 days remaining.
- The number of calendar days between today and your next birthday is then calculated.
- If you entered your birth year, the calculator also determines the age you will turn on that birthday.
Your birth year is not required to calculate the next occurrence of your birthday. The month and day are enough for the countdown. The year is only needed for age-related results.
This is different from calculating your current chronological age. If you want to know your age in years, months, and days, use the Age Calculator by Date of Birth.
Special Birthday Cases
If Your Birthday Has Already Passed This Year
If your birthday has already occurred during the current year, the calculator automatically moves to the next occurrence of that birthday in the following year.
For example, if today is September 3 and your birthday is May 20, May 20 of the current year has already passed. Your next birthday is therefore May 20 of the following year.
You do not need to change the year manually. The calculator handles the rollover automatically.
If Today Is Your Birthday
If today’s local calendar date matches your birthday, the result is 0 days remaining. The calculator recognizes that your birthday is happening today rather than immediately skipping ahead to next year’s birthday.
Your following birthday is still used when displaying future birthday dates, but today’s birthday remains the primary result.
February 29 Birthdays
February 29 occurs only in leap years. That means a recurring-date calculator needs a defined rule for February 29 birthdays during years in which February has only 28 days.
For this website, a birthday on February 29 is treated as February 28 during a non-leap year and February 29 during a leap year.
This is the calculation convention used by our tools. Other calculators, organizations, or legal jurisdictions may use a different convention for particular purposes.
For a more detailed explanation, see our guide to leap-year birthday age calculations.
How We Count the Days Until Your Birthday
The calculator uses calendar-day counting. It compares today’s local calendar date with the calendar date of your next birthday.
For example, if your birthday is tomorrow, the result is 1 day remaining even if you check late in the evening. If your birthday is today, the result is 0 days.
This approach focuses on whole calendar days rather than treating the countdown as a continuously decreasing number of 24-hour periods.
Why Two Birthday Calculators Can Differ by One Day
Two birthday calculators may occasionally produce slightly different answers because they do not all use the same counting rules.
Differences can occur when a calculator:
- counts today as part of the remaining days;
- uses exact timestamps instead of calendar dates;
- uses a different time zone or definition of when the birthday begins; or
- uses a different convention for February 29 birthdays.
Our calculator uses your local calendar date and counts whole calendar days until the next birthday date. You can read more about the site’s calculation rules on our Methodology and Accuracy page.
Birthday Calculator Examples
These examples show how the calculator treats common birthday situations.
| Situation | What the Calculator Does |
|---|---|
| Birthday is later this year | Uses the birthday date in the current year. |
| Birthday has already passed | Uses the same month and day in the following year. |
| Birthday is today | Shows 0 days remaining. |
| February 29 birthday in a non-leap year | Uses February 28 under this website’s calculation convention. |
Frequently Asked Questions
Do I need to enter my birth year?
No. Your birthday month and day are enough to calculate when your next birthday occurs and how many days remain. Your birth year is optional and is only needed to calculate the age you will turn.
Can I calculate someone else’s next birthday?
Yes. Enter the person’s birthday month and day. If you also know the birth year, the calculator can show the age that person will turn on the next birthday.
What day of the week will my birthday be?
The calculator shows the weekday of your next birthday along with its full calendar date. The upcoming-birthdays results also let you see how the weekday changes in future years.
Why does my birthday fall on a different weekday each year?
A normal year has 365 days, which equals 52 weeks plus one extra day. Because of that extra day, the same calendar date normally moves forward by one weekday the following year.
A leap year has 366 days. The additional February 29 can create a two-weekday shift for dates affected by the leap day.
How old will I be on my next birthday?
If you enter your birth year, the calculator shows the age you will reach on your next birthday. If you leave the year blank, the birthday countdown still works, but age-related results are not shown.
Does the Birthday Calculator store my birthday?
No. The birthday calculation is performed in your browser. The birthday information entered into the calculator is not stored by the calculator’s calculation code.
Why might another birthday calculator show a different number of days?
Another calculator may use a different counting convention, time zone, timestamp method, or February 29 rule. This calculator uses whole calendar days based on your local date and the calculation conventions described on our methodology page.
How is the Birthday Calculator different from the Age Calculator?
The Birthday Calculator focuses on your next birthday: when it occurs, how many days remain, what weekday it falls on, and the age you will turn.
The Age Calculator by Date of Birth instead calculates your current age, including years, months, and days.
Related Age and Birthday Resources
- Age Calculator by Date of Birth for your current age in years, months, and days.
- Methodology and Accuracy for the calculation rules used across the website.
- Leap Year Birthday Age Calculation for detailed guidance on February 29 birthdays.