This paper acquaints with a created application for generating Rainbow Tables and the results of testing Rainbow Tables, according to the length of the chosen chain. The paper presents a specialized application containing its own algorithms for reduction functions, changing the length of chain, generating Rainbow Tables and measuring the effectivity of the password search in detail. Within the executed tests, the dependence of Rainbow Tables size on the password length, the affection of the hash search by the size of the chosen chain and their links to collisions, which arise from the principle of using the reduction function, were observed. The results objectively describe the pros and cons of using Rainbow Tables and show the possibilities and restrictions for their effective usage.