How to calculate your exact age

The Age Calculator works out your exact age from your date of birth: years, months and days, plus how many days and weeks you have lived in total, and when your next birthday falls.

Everything runs in your browser — the dates you enter never leave your device.

Calculate your age

1. Open the Age Calculator.
2. Under Date of birth, fill in the three boxes: Day, Month and Year. Each box is labelled, so just follow the labels. You do not need leading zeros — 5 works the same as 05.
3. The As of date is already filled in with today’s date. Leave it as it is to get your current age.
4. Click Calculate age — or press Enter while typing in a field.

Your result appears below the button: your age in Years, Months and Days, followed by Total days lived, Total weeks lived and Next birthday.

Notes on entering dates

• Nothing is calculated while you type. The result only appears when you click Calculate age (or press Enter). If you edit a date after calculating, the old result is cleared so a stale number is never shown as current.
• Focus moves forward automatically once a box is full and valid, and stays inside the same date group. Backspace in an empty box moves back, and Tab works normally.
• A red box means an impossible value. If you enter a complete value that can never be valid — for example day 32, month 13, or year 0000 — that box turns red and focus does not advance until you fix it. The box clears back to normal as soon as the value becomes valid. Full error messages still only appear when you click Calculate age.
• What the errors mean:
  • Please enter your date of birth. — the date of birth is empty.
  • Enter a real date of birth. — the date does not exist, for example 31 February.
  • Date of birth cannot be after the "as of" date. — the birth date is later than the reference date.
  • Day must be between 1 and 31, Month must be between 1 and 12, Year must be 4 digits — one of the boxes is out of range.

Calculate age on another date

The As of date does not have to be today. Change it to any date to see your age on that date — for example, your age on a past date, or how old you will be on a future date. The same rule applies: the date of birth cannot be after the As of date.

The Next birthday line is worked out from the As of date as well. It shows how many days away your next birthday is, or tells you when it falls today.

Share your result

After a valid calculation, the share buttons become active:

• Click Share Result to create a shareable image of your result.
• Use the WhatsApp, Instagram, Telegram or X buttons to share it, or Copy image to copy the image and paste it elsewhere.

The share buttons stay disabled until you have a valid result, so you cannot accidentally share an empty or out-of-date calculation.

Tips

• If you only need your age in years, the large Years number is the answer — the months and days figures are the remainder on top of it.
• Double-check the year box: a four-digit year is required, and a mistyped year is the most common cause of a surprising result.