Enter two dates of birth to find who is older and the exact age gap in years, months and days, plus the total number of days apart. Use it for couples, siblings, friends or any two birthdays.
Enter your dates and select “Compare age difference” to see the result.
The age gap between two people is determined from their birth dates. The calculator orders the two dates, then measures the calendar interval from the earlier birth date to the later one.
The exact gap is decomposed into full calendar years, full months and remaining days. A second calculation counts the total elapsed days between the two birth dates.
Age difference = later birth date − earlier birth dateThis avoids subtracting rounded whole-year ages, which can look misleading around birthdays.
Person 1: 15 January 1990
Person 2: 20 October 1993
15 Jan 1990 → 15 Jan 1993 = 3 years
15 Jan 1993 → 15 Oct 1993 = 9 months
15 Oct 1993 → 20 Oct 1993 = 5 days
Age gap = 3 years, 9 months, 5 days = 1,374 total days.
Person 1 is older because Person 1 has the earlier birth date.
Enter a date of birth, or simply a birthday with its year, for each person. The result gives the gap in years, months and days, and you can turn it into months by multiplying the years by 12. It works the same way for partners, siblings, parents and children, or friends. Curious how big the gap is for well-known couples? See the celebrity age difference page.
Enter the two dates of birth. The age difference calculator measures the calendar interval from the earlier date to the later date and shows the gap in years, months and days plus the total difference in days.
Age difference = later birth date − earlier birth date, counted in full years, then months, then days. Subtracting only the two birth years is a quick estimate, but it can be off by up to a year because it ignores the birthdays.
The result shows years, months and days. To get the gap in months, multiply the years by 12 and add the months. For example, 3 years and 9 months is 45 months.
Enter each person’s date of birth. The calculation is the same for a husband and wife, two siblings, friends or colleagues, and it does not matter which date you enter first.
The elapsed-day gap between two birth dates stays the same. Subtracting two rounded ages in whole years can give a different-looking answer around birthdays, so this calculator compares the actual birth dates.
Yes. The result includes the total number of days between the two birth dates. Use the age in days calculator to compare how many days each person has lived on the same chosen date.
The calculation uses actual calendar dates. Full years are counted first, then months and remaining days; when the original day is absent in a month, its last day is used. Total days include February 29 where applicable.
No. Subtracting birth years ignores the month and day. For example, two people born in 1990 and 1993 are not automatically exactly three years apart; the exact gap depends on both full birth dates.
There is no single right number. What people consider a comfortable age gap varies between cultures, families and individuals, and the calculator only measures the gap. For legal questions about age, check the rules that apply where you live.
Yes. See the celebrity age difference page for the exact gaps of couples such as Elvis and Priscilla Presley or Alia Bhatt and Ranbir Kapoor.
Yes. If both people have the same date of birth, the age difference is zero years, zero months and zero days.
No. The calculation runs in your browser and the dates are not uploaded or saved by this website. The calculator is free to use.