Free speed, the key parameter in the modelling of pedestrian flow, is the speed that a pedestrian desires to walk at. In this study free speed of pedestrians considering characteristics such as age, gender, and with or without luggage in ascending and descending stairways located on platforms in suburban and intercity railway stations was examined. Due to difficulty in observing free speed directly, an approach for developing distributions of speeds at varying levels of pedestrian density is proposed to estimate free speed precisely.