The aim of this thesis was to develop a train length measurement system. With such a system it is possible for the railway traffic control to know on which passing loop a specific train can meet another train. It will lead to other benefits, such as less interference sensitive traffic and thus improved punctuality. This report describes the functionality and development process of an embedded train length measurement system. The Different methods are discussed and evaluated before the inductive method is choosen. The result is a stable system with good accuracy to a low cost. This thesis is made for the Swedish transport administration.