Age Calculator

An age calculator tells you exactly how old someone is from their date of birth — not just the year count, but the precise number of years, months and days. Enter a date of birth and the tool figures out the difference down to the day, correctly handling leap years and months of different lengths. By default it measures up to today, but you can set any 'age at' date to find an age on a past or future occasion.

This calculator does the calendar math the careful way: it borrows days from the previous month and months from the year so the result is always a valid years-months-days breakdown rather than a rough estimate. It also reports the total number of days lived, which is handy for milestone counts and quick comparisons.

Everything happens locally in your browser, so your birth date is never sent to a server or stored. Use it to answer 'how old am I', to work out a child's age in months for forms and milestones, to check eligibility cut-offs, or to plan birthdays and anniversaries. It is fast, free and private.