DAN-W is a windows-based geotechnical software tool used for dynamic runout analysis of rapid landslides and rock avalanches. The program accepts user-input data in the form of path slope and initial sliding mass geometries, and material properties based on eight types of rheologies. For pseudo-three-dimensional analysis, the width of the slide can also be specified. A Lagrangian solution of the integrated equations of motion is then implemented for thin elements of the flowing mass. The sliding mass is animated on the screen as the calculation progresses.