A Online age calculator by date of birth is a useful tool for calculating your age based on your date of birth. It can give you the answer in years, months, days, weeks, or even hours and minutes. The number of years is a useful tool for people who are trying to estimate their future age, or those who are simply curious about the age they are at present. There are several different types of age calculators available on the Internet. Each type has a different way of working out how old you are, so you can choose the one that suits your needs.