Age Calculator
Calculate your exact age in years, months, days, weeks, and hours. Find out what day of the week you were born on and countdown to your next birthday.
Date of Birth
Enter your date of birth
Calculate Age As Of
Leave blank to calculate age as of today
Your Age
34 years old
34 years, 11 months, 3 days
Birth Day Information
Details about your date of birth
Next Birthday Countdown
Understanding Age Calculations
Calculating age seems simple, but there are interesting nuances. This calculator provides your exact age in multiple time units, from years down to hours, giving you a comprehensive view of how much time has passed since your birth.
How Age is Calculated
Age is calculated by comparing your date of birth to a target date (usually today). The calculation accounts for:
- Years: Complete calendar years that have passed
- Months: Full months since your last birthday
- Days: Days since the start of the current month
- Leap Years: February 29th birthdays and leap year adjustments
Different Ways to Express Age
Age can be expressed in various units depending on the context:
Years, Months, and Days
The most common way to express age, especially for adults. Example: "34 years, 6 months, and 15 days old."
Total Days
Useful for precise calculations and comparing ages. A 30-year-old has lived approximately 10,950 days (not accounting for leap years).
Total Weeks
Sometimes used in medical contexts or for tracking milestones. There are approximately 52 weeks in a year.
Total Hours
A fun way to think about age. Someone who is 30 has lived over 262,800 hours!
What Day Were You Born On?
The day of the week you were born on is a fun fact many people don't know. Some cultures believe the day you're born influences your personality or destiny. There's even an old nursery rhyme: "Monday's child is fair of face, Tuesday's child is full of grace..."
Birthday Countdown
This calculator shows you exactly how many days remain until your next birthday, helping you plan celebrations or simply satisfy your curiosity. If today is your birthday, it will show "Happy Birthday!" and count down to next year.
Common Uses for Age Calculators
- Legal Requirements: Verify age for contracts, voting, driving, or drinking
- Retirement Planning: Calculate years until retirement or eligibility
- Medical Records: Precise age needed for pediatric or geriatric care
- Celebrations: Plan milestone birthdays (18th, 21st, 30th, etc.)
- Historical Context: Calculate how old someone was during historical events
- Relationships: Calculate age differences between people
Leap Year Birthdays
If you were born on February 29th, you only have a "real" birthday every four years! Leap day birthdays are rare (affecting about 1 in 1,461 people) and often celebrated on February 28th or March 1st in non-leap years.
Fun Age Facts
- By age 30, you've lived approximately 1 billion seconds
- The average human heart beats about 2.5 billion times by age 75
- Your actual birthday (the day you turn one year older) only happens once per year, but you're aging every single day
- In some cultures, everyone's age increases on New Year's Day rather than on individual birthdays
Important Notes
This calculator provides accurate age calculations based on the Gregorian calendar used in most of the world. Age calculations account for leap years (years divisible by 4, except century years not divisible by 400).
For legal purposes, always verify age requirements with official documentation. Some jurisdictions calculate age differently (e.g., considering you a year older on the day before your birthday).
The "day of birth" calculation uses modern calendar systems. Historical dates before the Gregorian calendar adoption (1582 in some countries, later in others) may have different interpretations.