Age Calculator
Calculate your exact age in years, months, days — and even hours — from your date of birth.
About the Age Calculator
How old are you, exactly? Not just in years, but in years, months, and days? The AlarmDaddy Age Calculator gives you a precise answer from your date of birth to today, or to any date you choose. It also shows your age in total months, weeks, days, hours, and even your next birthday countdown.
Enter your date of birth, and optionally a second date to calculate your age "as of" that day — useful for forms that ask your age on a specific cut-off date, school admissions, exam eligibility, or retirement planning. The calculator handles leap years and varying month lengths correctly, so the day count is always accurate. It is one of the most-used calculators on the site precisely because the question comes up everywhere: job applications, government forms, visa paperwork, and birthday planning.
How to use this calculator
- 1Enter your date of birth.
- 2Optionally change the "as of" date (defaults to today).
- 3Read your exact age in years, months, and days.
- 4See your age in total months, weeks, days, and hours, plus your next birthday countdown.
The formula
The calculator computes the difference month by month and day by day rather than dividing total days by 365. It borrows days from the previous month when the end day is earlier than the start day, and accounts for leap years, giving an exact years-months-days breakdown.