Abstract. GridTest is a framework for testing automated theorem provers using randomly generated formulas. It can be used to run tests locally, in a single computer, or in a computer grid. It automatically generates a report as a PostScript file which, among others, includes graphs for time comparison. We have found GridTest extremely useful for testing and comparing the performance of different automated theorem provers (for hybrid, modal, first order and description logics). We present GridTest in this framework description in the hope that it might be useful for the general community working in automated deduction. 1 Testing Automated Provers Testing a system is an invaluable source of information about its behaviour. But testing can be difficult and time consuming. This is particularly the case for systems that have to deal with very diverse input (where carrying out exhaustive testing would be impossible), and which need complex computation (that is, systems which are trying to so...