Debris flows pose a substantial threat to downstream communities in mountainous regions across the world, and there is a continued need for methods to delineate hazard zones associated with debris-flow inundation. Here we present ProDF, a reduced-complexity debris-flow inundation model. We calibrated and tested ProDF against observed debris-flow inundation from eight study sites across the western United States. While the debris flows at these sites varied in initiation mechanism, volume, and flow characteristics, results show that ProDF is capable of accurately reproducing observed inundation in different settings and geographic areas. ProDF reproduced observed inundation while maintaining computational efficiency, suggesting the model may be applicable in rapid hazard assessment scenarios.