Age Calculator
Calculate your exact age in years, months, and days — or work backwards to find a date of birth from a known age
Enter Your Details
This age calculator computes the precise difference between two dates in years, months, and days. It also shows total weeks lived, total days, and approximate hours, minutes, and seconds. Use it to check age eligibility, calculate retirement milestones, find how many days until your next birthday, or determine a date of birth from a known age.
How to Use the Age Calculator
Calculate Age
- Select your date and time of birth using the datetime picker.
- Choose a target date (defaults to the current date and time).
- Click Calculate Age to see your age in years, months, days, hours, and minutes — plus totals in weeks, days, and seconds.
Find Date of Birth
- Switch to Find Date of Birth mode.
- Enter your age in years, months, and days.
- Click Calculate to reveal your exact date and time of birth.
Why Use This Calculator?
Complete Precision
Time inclusion enables calculations down to the second — not just days.
Flexible Target Date / Time
Calculate age for any past or future moment, not just today.
Multiple Formats
Results display in years, months, days, total weeks, total days, hours, minutes, and seconds.
Fast & Free
No signup, no downloads — just fill in and get results instantly.
Mobile Friendly
Responsive design so it works seamlessly on phones, tablets, and desktops.
Example Uses
- Parents tracking an infant's age in weeks on a specific date.
- Determining a date of birth from a known age on a particular date.
- Professionals requiring exact age documentation for legal or medical purposes.
- Calculating total days lived or days remaining until a milestone age.