Age Calculator
Calculate age in years, months, days, and total days from a birth date. Free age calculator for any date.
How to use this age calculator
Age in whole years is what forms ask for; months and days matter for school cutoffs, benefits, and legal ages. Enter birth date and the date you care about—today, a birthday, or a deadline.
Formula
Worked example
Someone born January 1, 2000 is 26 on January 1, 2026.
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Frequently asked questions
Is this age calculator free?
Yes. It works instantly in your browser with no signup.
Are the results exact?
Results follow the stated formula, but real-world fees, timing, and rounding can vary.
How do you calculate age from a date of birth?
Count whole years, then remaining months and days using calendar months, not 365.25-day years. This age calculator also shows total days lived.
Does this use leap years?
Yes. It uses real calendar dates, so February 29 and leap days are handled correctly.
Can I calculate age on a future date?
Yes. Set the “age on date” field to a birthday, a school cutoff, or any future day.
Age in days vs years?
Total days is a simple timestamp difference. Years/months/days follow civil calendar rules.
Results are estimates for informational purposes and are not financial, legal, or professional advice. Last reviewed 2026-08-20.