resonances identifies mean-motion resonances of small bodies. It uses the REBOUND integrator (ascl:1110.016) and automatically identifies two-body and three-body mean-motion resonance in the Solar system. The package can be used for other possible planetary systems, including exoplanets. resonances accurately differentiates different types of resonances (pure, transient, uncertain) and provides an interface for mass tasks, such as finding resonant areas in a planetary system. The software can also plot time series and periodograms.