How the age calculator works
Enter a date of birth, and the age on today’s date appears instantly. To calculate an age on another day, for a form, a deadline or a past event, change the Age on date.
The result is counted the way people naturally count age:
- Whole years: the number of birthdays that have passed.
- Whole months: the monthly anniversaries of the birth date since the last birthday.
- Days: the days since the last monthly anniversary.
When the birth day does not exist in a shorter month, the monthly anniversary falls on that month’s last day. Someone born on 31 January 2000 was therefore exactly 1 month old on 29 February 2000 (a leap year), and someone born on 31 January 1995 is exactly 31 years and 3 months old on 30 April 2026.
Below the main result you also get the total number of months, weeks (plus remaining days), days and approximate hours, the weekday of birth, and the date, weekday and countdown of the next birthday.
Examples
| Date of birth | Age on | Result |
|---|---|---|
| 1 January 2000 | 6 October 2026 | 26 years, 9 months, 5 days |
| 15 March 1990 | 10 August 2026 | 36 years, 4 months, 26 days |
| 31 January 2000 | 29 February 2000 | 1 month exactly |
| 29 February 2004 | 28 February 2027 | 23 years (birthday counted on 28 February) |
For the first example, the 26th birthday was on 1 January 2026; nine monthly anniversaries later comes 1 October 2026, and 5 more days reach 6 October. The same span is 9,775 days, or 1,396 weeks and 3 days, 321 months in total and about 234,600 hours. The next birthday, the 27th, is Friday 1 January 2027, 87 days later.
With the 1 March option instead, the person born on 29 February 2004 is still 22 years, 11 months and 30 days old on 28 February 2027, and turns 23 the next day.
Common uses
- Checking an exact age for an application, an insurance form or an age limit.
- Working out a baby’s age in weeks or days, or the age at a past event.
- Answering “how old am I” in days for a milestone such as 10,000 days.
- Comparing ages on the Gregorian and Hijri calendars.
Good to know
- All dates use the Gregorian calendar with no time zone or daylight-saving effects, so the result is exact calendar arithmetic.
- On the Hijri calendar a year is about 11 days shorter, so the Hijri age can be higher: someone born on 1 January 2000 was 27 Hijri years, 7 months and 1 day old on 6 October 2026.
- Your date of birth stays on your device. If you use the share link, the date sits after the # in the address, which browsers never send to servers.
- To count down to your next birthday with a live clock, use the birthday countdown. To count the days between two dates that are not a birth date, use the days calculator. You can also convert Hijri and Gregorian dates on their own.