# Age in Years Calculator

Our age in years calculator can **find a person's age from their birthday and calculate the year they were born from their age**!

Have you ever wondered how old someone is when they say they were born in **1989**? Or did you try to guess someone's birth year from their age? With our calculator, you will be able to:

- Calculate age from birth date;
- Find birth year from age;
- Learn how to calculate age; and
- More about the date of birth calculation!

## How to calculate age

Calculating someone's age might seem straightforward, but it can get a bit more technical depending on how precise you want to be.

If we assume every month to have **exactly 31 days**, then we can get someone's age in days with the following formula:

`time = (years × 365) + (months × 31) + days`

where `years`

, `months`

, and `days`

are the **differences** between the person's birth date and **current year**, **month**, and **day**.

## How do I calculate someone's age in years?

To calculate a person's age in years:

- Take the difference between the
**current year**and their**birth year**:`years = current year - birth year`

. - Take the difference between the
**current month**and their**birth month**:`months = current month - birth month`

. - Take the difference between the
**current day**and their**birth day**:`days = current day - birth day`

. - Replace these differences in the age formula:
`age = (years × 365) + (months × 31) + days`

. This is the person's age**in days**. - Divide the result by
`365`

to get the age**in years**.

## Calculate age from birth date example

For example, if someone was born on **July 4th, 1989** and today was **July 5th, 2022** following the previous steps would result in:

**Years**difference:`2022 - 1989 = 33`

.*Note that this is the person's age if the date we're comparing to was their current year's birthday*.- The
**months**difference is`0`

in this example. - The
**days**difference is:`5 - 4 = 1`

. - Putting every difference in the corresponding variable inside the age formula:
`time = (33 × 365) + (0 × 31) + 1`

. - As a result, we get that the person is approximately
**≈ 12, 046 days old**. - We can divide by
`365`

to get the number in years:`12, 046 / 365 = 33.0027 years`

💡 Note that this is an approximation since we're not considering **leap years**. Our age in years calculator does include them in the calculation, and it can also output a person's age in many different units, such as: **days**, **hours**, **minutes**, and **seconds**!

## Calculate date of birth

Our age in years calculator doesn't only calculate age by birth date. **It can also work the other way around!**

To calculate the **date of birth**, simply input the person's age in **years, months, and days**, and our tool will automatically find their date of birth!

## Other useful tools

Feel free to check any of our chronological age if you enjoyed this age in years calculator:

- Age in weeks;
- Age in months;
- Age in years months and days;
- Age in days;
- Age in hours;
- Age in minutes; and
- Age in seconds.

## FAQ

### How old is the oldest person ever?

**122 years and 164 days**. The oldest person whose age was verified is Jeanne Calment, who lived **122 years and 164 days** from **February 21st, 1875** to **August 4th, 1997**.

### How old will I be in 2024 if I was born in 2002?

**22 years old**. If you were born in **2002** and wanted to find out how old you will be on your birthday in **2024**, simply **subtract your birth year from the year you're comparing to**: `2024 - 2002 = 22`

.