Age Calculator

Use this calculator to easily calculate your age, or the age of someone else. Just enter the birth date and click "calculate" to get your age in years, months, weeks, and days to use it as a "how old am I calculator" a.k.a. Pearson age calculator. Calculate the age of an object, such as a car or a house by entering the date of manufacturing or date of construction instead.

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How to calculate your age?

This free online age calculator makes it as easy as possible to calculate the age of a person, movable property, real estate, institution, company. All you need to enter is the date of birth / construction / establishment, etc., and click "Calculate age". The result will show you the number of full years, months, weeks, and days and is useful when answering questions like "how old am I in years", "how old am I in days" or "how old am I in months", "how old is X" and so on.

If you are asking yourself how old you are and want to get the answer by hand, you would need to make sure you account for leap years (366 instead of 365 days, February gets an extra day), so it can be a tedious task. If you are doing this calculation for a historical figure, then you would need to take into account possible differences in the calendar used when they were born and nowadays. For example, some Eastern European countries used the Julian calendar until they switched to the Gregorian one in late 19-th and early 20-th century (in different years for the different countries).

The age calculator by date of birth can also help you calculate your age at any given point in time after your date of birth (DoB). To do so, simply specify the date on which to calculate the age in the field labeled as such. If you need to know your age by the hour, minute or second, you can use our time duration calculator instead.

How old am I?

While looking deceptively simple, the answer to the above question is not nearly as straightforward as you think. But you might say that even 2-3 year-olds can use their fingers to answer that question, so how hard could it be, right? Answering "How old am I?" is actually pretty complex - read on to learn why.

This age calculator is based on the way human age is calculated in most Western countries. This means that when a person is born their age is 0 and it becomes 1 exactly a year from their birth, or as we say, on their birthday. The same goes for property, establishments, etc.

In other cultures, such as in East Asian, age reckoning is different. In some countries, a person begins their life at the age of 1 (by Western standard). Then another year is added to their age at New Year’s Day, even if this happens to be the second day of their life. This has largely to do with traditional fortune-telling methods and religion; and it could create a difference in a person’s age of one or two years between Western and Eastern counting systems.

To add to the confusion, when asked about their age some people present their complete age, while others present their running age. So for example, if at your last birthday you have completed your 21st year you might say that you are 21-years-old. However, you could also say you are 22-years-old, which would be your running age (as in the age you are currently towards completing).

It is not so obvious how to answer the "how old are you" question now, is it? Even our birthday calculator will only give you one of the possible answers when given your date of birth...

Running age vs. completed age

Whether you present your running age or completed age when asked how old you are is a matter of context, customs, or in some cases requirements of the document you need to fill, which may include legal instructions. Always follow those when provided, or ask if not sure.

Regardless, once you know what age you should present, you need to calculate it by using your date of birth. To calculate the completed age, determine how many full years have passed since your birth date. To compute the running age, simply add one to the completed age. It is as simple as that.

How old was I on a given date?

With the use of the "Calculate age on" field one can specify a date in the past to check how old they were on that date. For example, you might want to check how old you were at the opening ceremony of the 2012 Summer Olympic Games, just enter your date of birth in the first field, the starting date of the games in the second, and press calculate. For example, if you were born on Apr 10, 1985, you would have been 27 years old, or to be precise - 9970 days old.

Using the same field, a date in the future can be specified to calculate how old one would be at a given point in the future. For example, if you were born in 1994, in 2040 you would be 46 years old.

How many days have I lived?

Checking how many days, weeks, or months one has been alive is easy using this age calculator. The calculator outputs these numbers for all calculations performed, so simply enter your DoB and press the button to see the answer. As an example, a person born on Jan 1, 1988 would have been alive for exactly 12,511 days by Mar 04, 2022. That would make for a chronological age of 34 years, 3 months, and 2 days.

How old is X

Other than for yourself, an age calculator is useful to compute the age of someone or something else (a.k.a. "Pearson age"). E.g. if you are wondering how old Mariah Carey is, you would look up her date of birth, enter it in the "Birth date" field, and the tool will give you the answer. Alternatively, you can specify a date in the future to see, for example, how old she will be when you are fifty. You can do that for any person for whom the date of birth is known.

Likewise, you can calculate how old is a house, or a car, or even your grandma's refrigerator. It can also be used to determine the age of a company or institution, e.g. if you wonder how old is the US constitution, you can enter September 17, 1787 in the "birth date" field and get an answer in a second.

Cite this calculator & page

If you'd like to cite this online calculator resource and information as provided on the page, you can use the following citation:
Georgiev G.Z., "Age Calculator", [online] Available at: https://www.gigacalculator.com/calculators/age-calculator.php URL [Accessed Date: 27 Mar, 2023].