Age Calculator
Enter a date of birth to see the exact age in years, months and days — plus a countdown to the next birthday.
How to use the Age Calculator
- Open the date picker and choose a date of birth.
- Select Calculate age.
- Your exact age appears in years, months and days, along with total days, weeks and months lived, and your next birthday.
What is an age calculator?
An age calculator works out precisely how much time has passed between a date of birth and today — broken down into complete years, months and days, rather than just a single “X years old” figure. It also totals that time in different units and shows how many days remain until the next birthday.
How the calculation works
The calculator counts every complete year from the date of birth to today, then counts complete months within the current year, then whatever days remain — correctly handling different month lengths (28 to 31 days) and leap years along the way, including birthdays that fall on February 29.
Understanding your result
- Years / months / days is your age broken down the way people normally say it out loud.
- Total months / weeks / days express your whole age in a single unit, useful for babies or precise records.
- Next birthday shows the date and how many days remain until it.
Factors that affect the result
The result depends only on the date of birth you enter and today’s date on your device. Leap years can shift the exact day count slightly, and a birth date of February 29 is handled as a special case, celebrating on February 28 in non-leap years.
Common uses
This calculator is commonly used to check eligibility ages for school admission, jobs or government schemes, work out a baby’s exact age in weeks for medical appointments, or simply settle an argument about exactly how old someone is today.
Important notes & limitations
Dates are compared using your device’s local date, and a date of birth in the future isn’t accepted. Nothing you enter is stored or sent anywhere — the calculation happens entirely in your browser.
Frequently asked questions
What is an age calculator used for?
It's used to work out someone's exact age in years, months and days, check eligibility criteria that depend on age, or find out how many days are left until a birthday.
Does this account for leap years?
Yes. Leap years are handled automatically, including for people born on February 29.
Is my date of birth stored anywhere?
No. The calculation happens entirely in your browser and nothing is saved or sent to a server.
Why does my age in months look different from years × 12?
Total months counts every complete month you've lived, which can differ slightly from a simple multiplication once you account for the partial month at each end.
What happens if I was born on February 29?
In years without a February 29, your next birthday is shown as February 28 instead, so the countdown still makes sense.
Can I calculate age as of a future or past date instead of today?
This calculator always uses today's date for the calculation. For age as of a specific other date, a Date Difference calculator is the right tool.
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