Can I calculate age on a future or past date?

Yes. Change the 'age at date' field to any date to see how old someone was, or will be, on that day.

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Date & Time

Age Calculator

Find an exact age in years, months, and days from a date of birth — plus the total in months, weeks, and days, and a countdown to the next birthday.

Age

—

Total months—

Total weeks—

Total days—

Next birthday—

How it works

Exact age is the span between two dates, expressed as whole years, then whole months, then the leftover days. Because months vary in length and leap years add a day, the calculator borrows days from the previous month when needed, just as you would by hand.

years = full years between the two dates
months = full months after the last birthday
days = remaining days after the last whole month

Worked example

Someone born on 15 March 2000, measured on 9 August 2026, is 26 years, 4 months, and 25 days old — that is 26 full years, then March-to-July gives the months, and the days from 15 July to 9 August give the remainder.

Frequently asked questions

How is exact age calculated?

As whole years, then remaining whole months, then leftover days, accounting for month lengths and leap years.

Can I use a future or past date?

Yes — set the "age at date" field to any date to see age on that day.