Exactly how old?
Your age in years is easy. Your age in years, months and days, or in total days, is the kind of thing forms, school entry rules, insurance quotes and curious birthday cards ask for. This age calculator works it out from a date of birth, counts to today or to any date you pick, and shows how long until the next birthday.
It handles leap years, months of different lengths and 29 February birthdays, and it never sends the dates you enter anywhere.
How to use it
- Enter the date of birth. Type it or use the date picker.
- Leave Age on this date as today, or change it to find an age on another date.
- Read the age in years, then the exact years, months and days, the totals and the next birthday.
How age is counted
age = whole years since the birth date
then the whole months since the last birthday
then the days left overThis is the way people normally count age: you turn a year older on your birthday, not on 1 January. The months are calendar months, so a month from 15 May is 15 June. For someone born on 29 February, the calculator takes 28 February as the birthday in years that do not have a 29th.
Worked example: born 15 May 1990
Someone born on Tuesday 15 May 1990 checks their age on 29 October 2026.
- Whole years: the last birthday was 15 May 2026, so 36 years
- Then whole months: 15 May to 15 October, 5 months
- Then days: 15 October to 29 October, 14 days
They are 36 years, 5 months, 14 days old, which is 13,316 days in total. Their next birthday is Saturday 15 May 2027, 198 days away. They were born on a Tuesday.
Ages in other units
| Age | About this many months | About this many days |
|---|---|---|
| 1 year | 12 | 365 |
| 10 years | 120 | 3,652 |
| 18 years | 216 | 6,574 |
| 21 years | 252 | 7,670 |
| 30 years | 360 | 10,957 |
| 50 years | 600 | 18,262 |
The day counts vary by a day or two depending on how many leap years fall in the span. The calculator counts the exact days for your dates.
Things that trip people up
- Mixing up day and month. 05/04 means 5 April in many countries and May 4 in the US. The date picker avoids the problem.
- Counting age from the year only. Someone born in December 2000 is not 26 for most of 2026.
- Expecting months to be equal. Months have 28 to 31 days, so "5 months and 14 days" is not a fixed number of days.
- Some countries and cultures count age differently, for example starting at 1. This calculator uses the international convention.
Frequently asked questions
How do I calculate my age from my date of birth?
Count the whole years since your birth date, then the whole months since your last birthday, then the days left over. Born on 15 May 1990, on 29 October 2026 you are 36 years, 5 months and 14 days old. Enter your date of birth above and the calculator does it for any date.
How many days old am I?
Subtract your date of birth from today's date in days. Someone born on 15 May 1990 is 13,316 days old on 29 October 2026. The calculator shows the total in days, weeks and months next to your age in years, and counts every leap day exactly.
How does the calculator handle a 29 February birthday?
In years without a 29 February, it takes 28 February as the birthday, which many places also use for legal purposes. The age is counted the same way all year round, and the working notes when a leap day birthday is involved, so you can see how the answer was reached.
Can I find my age on a future date?
Yes. Change Age on this date to any date, past or future. That is handy for checking an age on a trip date, a school start date or the day a form will be signed. The next birthday line then counts from that date instead of today.
Related calculators
More free tools from CloveDesk
CloveDesk gives freelancers and small teams one place for quotes, e-signatures, invoices, files and a portal for each client.
Last updated: