Lottolibrary's lottery odds calculator tool relies on a branch of mathematics called probability theory.
In a fair game of lottery, each number has an equal chance to be drawn, which means that lotteries follow the so-called discrete uniform distribution. The exact odds of winning a certain prize can be calculated by dividing the number of winning combinations by the number of all possible combinations. These two numbers can be easily computed using some of the basic formulas of combinatorics.