# Age Calculator by Date of Birth - How Old Am I?

Calculate your exact age and learn the answer to the question: How old am I?

## What Is the Meaning of Age?

Age is a term used to describe the length of time that something or someone has existed or been alive for. Every person has an age which is defined as the number of years they have lived through in full since their date of birth. Since you pass your date of birth every year (also known as your birthday), you are classified as one year older every time. How old you are is known as your age.

For example, if you were born in the year 2000 and it is now 2021, you would be either 20 or 21 years old. Which age you are depends on when your birthday is and whether that date has passed. If your birthday was in February and it is now March, you are 21. If it is still January, you are 20.

Humans are not the only ones that have ages. All living things – including animals, mammals, and other organisms – have an age. Non-living things have an age, too. For example, an alarm clock online that was invented and built 5 years ago is 5 years old (with an age of 5).

## How Do You Determine Age from Year?

There are two main ways to determine the age of something from the year it is. You can either:

1. Do a calculation in your head
2. Use an online age calculator

### How to Easily Determine Age from Year Using Math

There are two easy ways to determine someone's age from the year using maths. If you are working out someone's age using two dates from the same century, you can subtract the person's birth year from the current year.

For example, if someone is born in 1990 and it is 1999, you can subtract 1990 from 1999 or just 90 from 99, to get 9 – which is the person's age if their birthday has already passed in that year. If the person's birthday has not yet passed, you subtract another 1 from this number, leaving you with 8.

If you are working out your age using two dates from different centuries, it is easier to add up to the century mark and then add on the last two digits from the current year.

For example, if someone was born in 1990 and the current year is 2010, you calculate how many years there are from 1990 to 2000 (by adding or subtracting), which would leave you with 10 years. Then, you add or subtract to work out how many years there are between the year 2000 and the year 2010, which is another 10. So, adding 10 + 10 means the person's age is 20 if their birthday has already passed. If it hasn't yet passed, the person is 19, as you subtract another 1.

### How to Easily Determine Age from Year Using an Online Age Calculator

Using an online Age Calculator is an easy way of figuring out how old you or someone else is (or will be) on an exact date. When using an online Age Calculator, you'll usually need to enter:

• The person's birth date
• Today's date or the date you want to calculate someone's age on

The calculator will then show you how old you are in years.

## How Do You Calculate Your Age by Hand?

Many people believe that you can determine age by looking at someone's life line on their palm. To calculate your age from your hands, you need to:

• Locate the life line and heart line on your hand
• Work out the ratio between the two lines
• Use the ratio to work out your potential age

Using the table below, you can work out how old the person could be based on the life line to heart line ratio.

RatioPotential Age
0.34 or 0.3876 years
0.3571 years
0.3664 or 81 years
0.3768 or 79 years
0.3974 years
0.4180 years

## What is the Birthday Age Calculator?

The Birthday Age Calculator is a quick and easy way to calculate your age or someone else's age. Using your birth date and a date you want to calculate your exact age at, you can answer the question, "How old was I on this date?" You can also answer the question, "How old will I be on this date?" using the online Birthday Age Calculator.

## How to Use the Age Calculator

Using the Age Calculator is an easy way to answer the question, "How old was I on this date?"

To calculate your age, simply: