Age calculator
Exact age in years, months and days from a date of birth, with total days and hours, the weekday you were born, next-birthday countdown and Hijri birthday.
Your age
Enter your date of birth and the calculator gives your exact age in calendar years, months and days, counted the way birthdays and legal ages are: whole months first, then the days left over. Someone born on 15 May 1990 is 36 years, 4 months and 6 days old on 21 September 2026, because 15 September 2026 completes the fourth month after their 36th birthday and six more days follow.
The same result lists your age as a total of months, weeks, days and hours (days × 24), the day of the week you were born, the date of your next birthday with a countdown, and your date of birth in the Hijri (Umm al-Qura) calendar with your age in full lunar years. A Hijri year is about 354 days, 11 days shorter than a Gregorian year, so a 36-year-old is already 37 in Hijri years.
Change the “Calculate age on” date to find your age on any other day: the cut-off date of a school intake, a visa or pension rule, or a future birthday. People born on 29 February have their birthday counted on 28 February in common years, which is the rule most legal systems use; the result says so when it applies. Everything is calculated in your browser.
How to use it
- Enter your date of birth.
- Leave “Calculate age on” empty to use today, or pick another date.
- Read your age in years, months and days at the top; the table below shows totals, the weekday you were born, the next birthday countdown and the Hijri dates.
- Use Copy result to paste the figures into a form or message.
Frequently asked questions
How is exact age calculated?
By counting whole calendar months from the date of birth, then the days left over. From 15 May 1990 to 21 September 2026 there are 436 whole months (36 years and 4 months, reaching 15 September 2026), plus 6 days. Counting whole months avoids the error of dividing days by 30 or 365.25.
What if I was born on 29 February?
In common years there is no 29 February, so the calculator treats 28 February as your birthday, which is how the UK, most US states and many other jurisdictions count legal age. A few count 1 March instead; if a rule you are checking is that strict, look at the result for the day after.
Why is my Hijri age higher than my normal age?
The Hijri calendar follows the moon, so its year is about 354 or 355 days, roughly 11 days shorter than the Gregorian year. Every 33 Gregorian years add up to about 34 Hijri years. The calculator converts both dates with the Umm al-Qura calendar used officially in Saudi Arabia and counts the full Hijri years between them.
Does the calculator use the time of birth?
No. It works in whole days, so the totals in hours are days × 24. If you need the difference down to the hour, add the hours between your birth time and now yourself.
Can I calculate my age on a future date?
Yes. Set “Calculate age on” to any date after your birthday, for example the start of a school year or the closing date of an application, and the result shows how old you will be that day.
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