Depending on the purpose different definitions of length L are used:
1. (L) – 96% of the total length on a waterline at 85% of the least moulded depth measured from the top of the keel, or the length from the foreside of the stem to the axis of the rudderstock on that waterline, if that be grater, (MARPOL, ICLL).
2. According to SOLAS length of the ship is the length measured between perpendiculars taken at the extremities of the deepest subdivision load line.