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Age Calculator by Year
Birth year and target year
Example: born June 15, 1990 — turns 36 in 2026 (35 until June 15, 2026).
Behind the numbers
How your age in a year is calculated
Your age in a year is the target year minus your birth year, but only after your birthday that year. Before your birthday, you are one year younger. If you enter only a birth year, the calculator gives the age you turn in the target year. If you add the birth month and day, it also tells you the age at the start of the year and the exact birthday in the target year.
For a birth year of 1990 and a target year of 2026: 2026 − 1990 = 36. Because the birthday is June 15, the person is 35 from January 1 through June 14, 2026, and 36 from June 15, 2026 onward. The age on any date in the target year is the target year minus the birth year, minus 1 if the birthday has not happened yet that year.
Examples
Example ages across the years
| Year | Age (born June 15, 1990) | Note |
|---|---|---|
| 2000 | 10 | Turned 10 on June 15, 2000 |
| 2005 | 15 | Turned 15 on June 15, 2005 |
| 2010 | 20 | Turned 20 on June 15, 2010 |
| 2020 | 30 | Turned 30 on June 15, 2020 |
| 2026 | 36 | Turns 36 on June 15, 2026 |
| 2030 | 40 | Turns 40 on June 15, 2030 |
| 2040 | 50 | Turns 50 on June 15, 2040 |
| 2050 | 60 | Turns 60 on June 15, 2050 |
Tips
For school enrollment, sports leagues, and official forms, the age that counts is usually the age on a specific cutoff date — check that date, not just the year.
If you only know the birth year, remember the result is the age the person turns in that year, which may be one more than their age early in the year.
For a future year, the same rule applies: subtract the birth year and check whether the birthday falls before or after the date you care about.
Leap-day birthdays (February 29) are usually observed on February 28 or March 1 in other years; the year count is the same either way.
Good to know
Frequently asked questions
How old will I be in 2030?
Subtract your birth year from 2030. If you were born in 1990, you turn 40 in 2030. If your birthday is late in the year, you are still 39 for most of 2030 until that birthday.
How old was I in 2010?
Subtract your birth year from 2010. Someone born in 1990 turned 20 in 2010. Enter the year in this calculator and it gives the exact figure, including the before-and-after birthday split when you add the month and day.
Why does the calculator show two ages for one year?
Because you have a different age before and after your birthday. In any year you spend part of the year at one age and the rest at the next age, so both numbers are correct for different dates in that year.
What if I only know the birth year?
Leave the month and day blank. The calculator then shows the age the person turns in the target year, which is the most common way people ask the question.