Question 1

How is age calculated in years, months and days?

Accepted Answer

Start with the difference in full years. Then count the remaining months from your last birthday. Finally count the remaining days from the start of the current month. For example, if you were born on 10 March 1990 and today is 25 September 2026, you are 36 years, 6 months and 15 days old.

Question 2

How do I calculate my age in days?

Accepted Answer

Multiply your age in years by 365, add the days for each leap year you have lived through, then add the remaining days since your last birthday. The easiest way is to subtract your date of birth from today's date — most people's ages fall between 7,000 and 40,000 days.

Question 3

What day of the week was I born?

Accepted Answer

Enter your date of birth above and the calculator shows you. You can also work it out using Zeller's congruence or Tomohiko Sakamoto's algorithm, but those involve a bit of maths — the calculator does it instantly.

Question 4

How many days until my next birthday?

Accepted Answer

The calculator counts the days from today to your next birthday automatically. If your birthday is later this calendar year, it subtracts today from that date. If it has already passed this year, it counts to next year's date instead.

Question 5

What are the key age milestones in the UK?

Accepted Answer

Some significant UK age thresholds: 16 — can leave school, get married with parental consent, consent to medical treatment; 17 — can learn to drive; 18 — full adult rights, can vote, buy alcohol, enter contracts; 21 — hire a car more easily, some insurance products become available; 22 — National Living Wage rate increases; 25 — full NLW applies regardless of hours; 66 — State Pension age (rising to 67 by 2028).

Question 6

How is age calculated for legal purposes in the UK?

Accepted Answer

In UK law, you reach an age on the anniversary of your birthday — the day itself, not the day before. So if you were born on 1 January, you legally become 18 on 1 January, 18 years later. This matters for driving licences, voting, and other age-gated rights.

Age Calculator — How Old Am I in Years, Months and Days