How does the calculator handle leap years?

It counts real calendar months and days, so 29 February birthdays and leap-year differences are handled exactly.

Can I calculate the time between any two dates?

Yes — set the “as of” date to anything you like. The tool then reports the exact span between the two dates.

Why does the months figure differ between people with the same birthday month?

Months have different lengths, so “X months, Y days” depends on the actual calendar months crossed, not a fixed 30-day month.

Age Calculator

Work out an exact age in years, months and days from a date of birth, plus total days lived and a countdown to the next birthday.

Date of birth As of

—Years

—Months

—Days

—Total days

How to use the Age Calculator

Enter the date of birth (or any start date).
Optionally change the “as of” date — it defaults to today.
Read the exact age in years, months and days, total days lived, and days until the next birthday.

About this tool

Age sounds simple until you need it exactly — for a form, a visa application, a pension date or a child’s school cutoff. Counting calendar months by hand across leap years is fiddly and error-prone; this calculator does it precisely from real calendar arithmetic.

Beyond the headline years-months-days figure, the tool shows your age in total days — surprisingly satisfying to know — and counts down to the next birthday, correctly rolling over the year and handling 29 February birthdays in non-leap years.

It also works as a general date-difference calculator: set the “as of” date to any date to measure spans for contracts, anniversaries, project durations or historical events.

Frequently asked questions

How does the calculator handle leap years?: It counts real calendar months and days, so 29 February birthdays and leap-year differences are handled exactly.
Can I calculate the time between any two dates?: Yes — set the “as of” date to anything you like. The tool then reports the exact span between the two dates.
Why does the months figure differ between people with the same birthday month?: Months have different lengths, so “X months, Y days” depends on the actual calendar months crossed, not a fixed 30-day month.

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