Being a father or a mother is a very significant milestone in a couple's life and in case you are going to be a parent for the first time then you might feel more excitement for this proud moment of your life. So you would be anxious to know several aspect of pregnancy and might be interested to calculate when the approximate date your baby will take birth. To do an approximate calculation there are several methods and a pregnancy test calculator helps you to calculate the approximate date which is based on some basic principles. The basic principles which is involved in the pregnancy test calculator is the approximation of the normal gestation period. There are many pregnancy test calculators available and even your gynecologist might have already told you the approximate date of the birth of the baby. Still you can take the help of the pregnancy test calculator to calculate the approximate date of birth date of the baby. The pregnancy test calculator is absolutely user friendly and available to use free of cost. However there is no guarantee that the date suggested is the one when your baby will be born. There are several factors associated with the pregnancy and birth of the baby and thus this can be few days more or less than the actual date come out as a result of the pregnancy test calculation. You can find this pregnancy test calculator online. You may find some online pregnancy test calculator which is FDA approved and that might charge you very minimally. bit its worth spending. The pregnancy test calculator would ask you few questions, Those questions would be like, typically  how long your monthly cycle is  and what is the average length of the luteal phase. There are also help buttons if you do not understand the meaning of any particular term. By clicking on that button you will be taken to a page where you can submit your query to get an immediate help about the term. Then the pregnancy test calculator might ask you when was the last date of your menstrual cycle. There will be drop down boxes for registering the exact date , month and year, so that you can easily and quickly enter the information asked for. The pregnancy test calculator might also ask you about the approximate date of the intercourse and may also ask for if you had intercourse in other days of the week plus in the range of  or minus two days. So when you provide all these information, the pregnancy test calculator will take few seconds to give you the approximate date of the birth date of your baby.