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Age calculator
Exact age in years, months and days, and days to the next birthday.
Quick answer
Your exact age is the time from your date of birth to a chosen date, counted in years, months and days. Formula: Subtract the date of birth from the later date, year by year, month by month and day by day. Someone born on 15 June 1995 is 30 years, 6 months and 17 days old on 1 January 2026.
Read the guide: How to calculate your exact age in years and days
Your age
31 years, 4 months, 30 days
- Total days lived
- 11,475
- Total weeks
- 1,639
- Next birthday in
- 213 days (Tuesday, 15 June 2027)
- Born on a
- Thursday
How is age calculated?
The calculator counts complete years first, then complete months, then the days left over.
Change the second date to find your age on any day: a past exam date, a form deadline or a future date.
People born on 29 February have their birthday on 1 March in non-leap years for the "next birthday" count.
What is the formula for age?
- Subtract the date of birth from the later date, year by year, month by month and day by day
- If the day count goes negative, borrow the length of the previous month; if the month count does, borrow a year
Can you show a worked example of age?
Born 15 June 1995, measured on 1 January 2026: 30 years to 15 June 2025, 6 months more to 15 December 2025 and 17 days to 1 January 2026, so 30 years, 6 months and 17 days.
How many days old is someone at a given age?
Days lived by a person born on 1 January 2000, on their birthday. Leap days are counted.
| Age | Days lived |
|---|---|
| 1 year | 366 |
| 5 years | 1,827 |
| 10 years | 3,653 |
| 18 years | 6,575 |
| 21 years | 7,671 |
| 25 years | 9,132 |
| 30 years | 10,958 |
| 40 years | 14,610 |
| 50 years | 18,263 |
| 60 years | 21,915 |
Common questions
How do I calculate my exact age?
Subtract your birth date from today’s date in years, months and days. Enter your date of birth and the calculator does it for you.
Can I find my age on a past or future date?
Yes. Change "Age on this date" to the day you need, such as a form cut-off date.
How many days old am I?
The total days lived is shown under your age.
What about leap years?
They are handled: February 29 is counted in the day totals and the months are worked out on real month lengths.