The relational model and especially the relational algebra is the fundament of each relational database system and thus content of almost every database lecture. Even though there exist a few tools allowing to experiment with relational algebra, a common way to learn it is still by formulating queries on paper, without the option of checking them for syntax or even executing them. To fill this gap and to support students in their learning process, we propose RelaX, a webbased tool which is capable of executing arbitrary relational algebra statements on arbitrary datasets. By drawing interactive operator trees corresponding to the queries, it is also possible to compute the final result in a step-by-step manner. Finally, RelaX is also equipped to execute SQL queries and to automatically translate them to relational algebra.