AbstractThis paper presents the FBT (FIL to Buechi automaton Translator) tool which automatically translates any formula from FIL (Future Interval Logic) into its semantically equivalent Buechi automaton. There are two advantages of using this logic for specifying and verifying system properties instead of other more traditional and extended temporal logics, such as LTL (Linear Temporal Logic): firstly, it allows a succinct construction of specific temporal contexts, where certain properties must be evaluated, thanks to its key element, the interval, and secondly, it also permits a natural, intuitive, graphical representation. The underlying algorithm of the tool is based on the tableau method and is specially intended for application in on-the-fly model checking. In addition to a description of the design and implementation structure of FBT, we also present some experimental results obtained by our tool, and compare these results with the ones produced by an other tool of similar characteristics (i.e. based on an on-the-fly tableau algorithm), but for LTL.