Age Calculator
Find your exact age in years, months, and days from your date of birth.
Written by Golam Rabbani, Founder & Lead Engineer
How to use this age calculator
- Enter your date of birth using the date picker.
- Press Calculate to see your age in years, months, and days.
- Read the result panel for your exact age and days until your next birthday.
- Use Copy to put the result on your clipboard, or Reset to start over.
About this age calculator
The age calculator takes your date of birth and returns your exact age broken into years, months, and days, plus the number of days until your next birthday. Everything runs in your browser against the current date on your device, so the result updates whenever you re-open the page.
Behind the scenes the age calculator subtracts your date of birth from today using calendar arithmetic, not a flat 365-day year. It first takes the year difference, then borrows a month when the current day-of-month is earlier than your birth day-of-month, then borrows a year when the current month is earlier than your birth month. This is the same method registry offices and immigration forms use, which is why the day count never exceeds the number of days in the relevant previous month.
For example, if you were born on 1990-05-15 and today is 2026-05-27, the tool returns 36 years, 0 months, 12 days, and shows that your next birthday is in 353 days. This is useful for filling in forms that ask for age in years and months, working out school year eligibility, planning birthday milestones, and answering the everyday "exactly how old am I" question.
FAQ
- How does the age calculator work?
- It subtracts your date of birth from today's date using calendar arithmetic — counting whole years first, then remaining months, then remaining days — so the answer matches how age is recorded on official forms rather than being a flat division of days by 365.
- Why is the day count sometimes 28, 30, or 31?
- When the current day-of-month is earlier than your birth day-of-month, the calculator borrows the number of days from the previous month. That month has 28, 30, or 31 days depending on which month it is, so the day component of your age varies accordingly.
- What happens if I enter a date in the future?
- The date input is capped at today, and if you somehow submit a future date the tool shows an error rather than a negative age. Pick a date on or before today to get a valid result.
- Does the age calculator store my date of birth?
- No. The age calculator runs entirely in your browser. Your date of birth is never sent to a server, logged, or saved between visits — closing the page clears it.
- Is the age calculator free?
- Yes. It is free to use with no signup, no account, and no usage limit.
- How many days until my next birthday?
- The tool computes this for you: it finds the next occurrence of your birth month and day after today and counts the days between. If today is your birthday, the next-birthday counter shows 365 (or 366 in a leap year).