This paper concerns about Keystroke Dynamics database quality which can vary depending on researchers’ approach. Database classification has been presented and the most popular publicly available databases are introduced. Authors’ database is presented and compared with the others. This paper introduces new database and compares the results of the same algorithms obtained on two almost identical databases. The results of comparison are discussed in terms of keystroke dynamics dataset quality. It has been proven that different methods can produce results of unanticipated kind.