We present a web-based tool for a fine-grained analysis of the quality of public transport coverage. Employing an efficient graph-based transport network representation and a fast, modified Dijkstra-based journey planning algorithm, the tool calculates four public transport accessibility indices: journey duration, service frequency, the number of transfers, and a combined, overall index. Together, the indices give an accurate picture of the user-perceived accessibility by public transport in the area and time of interest.