How to use the age calculator
- Pick the date of birth in the first box. On a phone, tap the box to open a date picker.
- Leave the second box on today's date, or change it to see how old someone was or will be on a different day.
- Your exact age appears at once, with extra details like total days lived and the next birthday.
Why your age in days is interesting
Most people never think about it, but you turn 10,000 days old at roughly 27 years and 4 months. Some people celebrate it as a second birthday. Your 1,000th week arrives at about 19 years and 2 months. Type your birthday above and keep an eye on the total days to spot your own milestones.
When you need an exact age
- Forms and applications: visas, insurance quotes and job applications often ask for age on a specific date.
- School and sports: many schools and clubs use a cut off date to decide which year group or age band a child belongs to.
- Baby milestones: parents often track age in weeks and months during the first two years.
- Retirement planning: pension ages can depend on an exact date of birth.
How the months and days are counted
Months have different lengths, so "1 month" is not a fixed number of days. We count calendar months. From 15 January to 15 February is one month, even though it is 31 days, and from 15 February to 15 March is also one month, even though it is only 28 or 29. Leftover days are counted after the last full month. This matches how people normally talk about age.