Birthday Calculator
Count down to your next birthday — plus the day you were born and the age you're turning.
Fill in the fields above to see your result instantly.
Enter your date of birth and this birthday calculator counts the days until your next birthday, tells you which day of the week you were born on, the age you're about to turn, and even your half-birthday. It handles February 29 birthdays by rolling to the next real anniversary. Like every tool here, the math runs in your browser and nothing is saved.
How to use the Birthday Calculator
- 1
Enter your date of birth
Pick the day you were born.
- 2
See the countdown
The number of days until your next birthday appears instantly.
- 3
Explore the extras
Check the weekday you were born, the age you're turning, your half-birthday, and your star sign.
Examples
Frequently asked questions
How many days until my birthday?
The calculator finds your next birthday from today's date and counts the whole days remaining. If today is your birthday, it says so.
What if I was born on February 29?
Leap-day birthdays roll forward to the next year that actually has a February 29, so the countdown lands on a real date.
What is a half-birthday?
Your half-birthday is the date six months from your birthday — popular for kids whose birthdays fall in school holidays. The calculator shows the next one coming up.
How is the day of the week I was born found?
From the calendar date itself — every date maps to exactly one weekday, which the calculator looks up directly.