Check how to find the probability of single events.Discover how to use the probability calculator properly.As long as you know how to find the probability of individual events, it will save you a lot of time. Our probability calculator gives you six scenarios, plus 6 more when you enter in how many times the 'die is cast', so to speak. For example, if the chance of A happening is 50%, and the same for B, what are the chances of both happening, only one happening, at least one happening, or neither happening, and so on. With the probability calculator, you can investigate the relationships of likelihood between two separate events.