Age Difference Calculator.

Compare two dates of birth to see the exact age difference.

Understanding age differences.

Age differences between two people are often quoted simply in years, but the actual difference depends on the specific birth dates. Two people both "born in 1990" could have an age difference of nearly 12 months if one was born in January and the other in December.

Our calculator provides the precise difference down to the day, which is more useful for legal purposes (age of consent, retirement eligibility), educational cutoffs (school enrollment dates), and personal curiosity.

This tool is useful for couples curious about their exact age gap, parents comparing children's ages, or anyone needing to calculate the precise difference between two dates of birth. For a general duration between any two dates, see our Date Duration Calculator.

Frequently asked questions.

Quick answers to common questions about age calculation.

How does the Age Difference Calculator work?
Enter two dates of birth, and the calculator determines the exact difference in years, months, and days. It also identifies which person is older and shows the difference as total days, weeks, and months.
Can I compare ages of people born in different centuries?
Yes. The calculator works with any valid dates, including dates from different centuries. You can compare someone born in 1940 with someone born in 2005, for example.
Does the order of the dates matter?
No. The calculator automatically identifies which date is earlier and labels the results accordingly. You can enter the dates in any order.
What if both people have the same birthday?
If both dates of birth are identical, the calculator will show a difference of 0 years, 0 months, and 0 days.
How is this different from the Date Duration Calculator?
The Date Duration Calculator computes the time between any two dates. The Age Difference Calculator is specifically designed for comparing two people's ages and clearly shows who is older.

Related tools.

Explore our other free date and age calculators.

Age Calculator

Calculate your exact age in years, months, and days.

Date Duration Calculator

Find the exact duration between any two dates.

Birthday Countdown

Count down the days until your next birthday.