Age calculator
Your exact age in years, months and days — and everything else a birth date can tell you.
Only know the year? See age by birth year.
Enter a date of birth. The result appears as you type — no button needed.
How exact age is worked out
Born 14 Jul 1990. We want the age on 5 Mar 2026.
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Questions
How is exact age calculated?
Count the whole years since your birthday, then the whole months since your last birthday, then the days left over. Because months have different lengths, the days figure is counted from the same date in the most recent month, not by dividing by 30.
What if I was born on 29 February?
In years without a 29 February, this calculator treats 28 February as your birthday, which is also how most legal systems handle it for things like driving age. Some countries use 1 March instead.
Can I calculate my age on a past or future date?
Yes. Change the "Age on" date to any day — for example the start date of a school year, a retirement date, or an eligibility cutoff — and every figure updates.
Is my date of birth stored anywhere?
Only on your own device, so the calculators remember it between visits. Nothing is sent to a server; clear it with the "Forget my date" link at any time.
How do I calculate age from date of birth?
Subtract the birth year from the current year, then subtract one more if this year's birthday hasn't happened yet. For months and days, count whole months from your last birthday and then the days left over. The calculator above does all three steps instantly.
How do I calculate a date of birth from an age?
Subtract the age in years from today's date, which gives the latest possible birth date; the person was born within the 12 months before that. If you also know the months and days, subtract those too for the exact date.
How do I check that an age is correct?
Count forward from the date of birth: each birthday reached adds a year. If the most recent birthday is still to come this year, the age is one less than the simple year difference.
Why is my age in days different on another calculator?
Some tools count the birth day itself or include today. This calculator counts full days elapsed since midnight on the day you were born, which is the standard convention.