Age Calculator
Calculate your exact age in years, months and days from your date of birth.
Your Age
How this age calculator works
Enter your date of birth and the date you want to calculate your age on. The calculator shows your exact age in years, months and days, together with approximate total months, completed weeks and total days.
How to Calculate Your Exact Age
Knowing your exact age involves more than simply subtracting your birth year from the current year. Months and days also need to be considered, especially when your birthday has not yet occurred during the current year.
To calculate your age, enter your date of birth in the first field. Then choose the date on which you want your age calculated. This can be today or another date. Click the Calculate Age button to see the result.
The result provides a clearer breakdown of how much time has passed since your date of birth.
Understanding Years, Months, and Days
A person's age is normally expressed in completed years. However, there are many situations where knowing the additional months and days can be useful.
For example, someone may be 40 completed years old but also several months and days beyond their most recent birthday. Showing these additional units provides a more precise result than displaying years alone.
Calendar calculations can become complicated because months have different lengths. Some contain 30 days, others contain 31 days, and February normally contains 28 days. During a leap year, February contains 29 days.
Because of these differences, simply converting every month into the same number of days does not always produce an exact calendar-based result.
For general information about age, dates, and time measurement, you can explore the National Institute of Standards and Technology’s time resources.
Example Age Calculation
Suppose a person was born on January 15, 1990, and wants to know their age on September 30, 2026.
The calculation first counts the completed years between the two dates. It then considers the additional completed months and remaining days.
This method provides a useful calendar-based breakdown rather than only showing the difference between the two year numbers.
You can also select a different calculation date if you need to determine someone's age on a previous or future date.
The Age Calculator makes this process easier by automatically comparing the selected dates and displaying the result.
Why Calculate Age on a Specific Date?
There are many reasons you may need to know how old someone was or will be on a particular date.
For example, you may want to check an age for a birthday, school enrollment, retirement planning, an application, an event, a membership, or general record keeping.
Selecting a specific calculation date also makes the tool useful for historical questions. Instead of calculating only today's age, you can enter another date and determine the age at that point in time.
Always verify official age requirements directly with the relevant organization when the result is being used for an important legal, financial, medical, educational, or administrative purpose.
Birthdays and Leap Years
Leap years can affect date calculations for people born near the end of February. A leap year normally occurs every four years, although calendar rules include exceptions for certain century years.
People born on February 29 may celebrate or recognize their birthday differently during non-leap years depending on personal preference and applicable rules.
For official purposes, age-related requirements may depend on laws or policies in a particular location. The result provided here is intended as a convenient informational calculation rather than legal advice.
Useful Tips
Before calculating, check that your birth date has been entered correctly. Even a small mistake in the day, month, or year can change the result.
Also confirm the Calculate Age On date, particularly when you are checking an age for a historical event or future date.
If you want to start again, use the Reset button and enter new dates.
A Simple Tool for Everyday Use
This tool is designed to make date-of-birth calculations quick and straightforward. You do not need to manually count different month lengths or work through calendar dates yourself.
Whether you are checking your current age, planning for an upcoming birthday, or determining an age on another date, the calculator provides a convenient way to obtain the result in seconds.
Our Age Calculator provides a quick way to check your age without manually working through years, months, and days.
Explore more helpful calculators and everyday tools on our Calculators page.