A measuring device adapted to measure a distance between an edge of a platform and a sill of a rail vehicle , the measuring device comprising a measuring tool adapted to measure a first distance (E 1 ) between the edge of the platform and the sill of the rail vehicle , the first distance (E 1 ) being measured in a transverse direction (Y) of the rail vehicle , the measuring tool comprising: - a support adapted to be installed on the edge of the dock , the support having at least one locating surface for abutting the dock in the transverse direction (Y) and in an elevation direction (Z) substantially normal to the transverse direction (Y); - a movable part mounted on the support and translatable relative to the support in a first direction (A) between a plurality of positions, including a measuring position in which the support is intended to abut the edge of the dock and the movable part is intended to abut the sill of the rail vehicle ; and - an indicator system of the first deviation (E 1 ) adapted to provide first information representative of the first deviation (E 1 ) when the movable part is in the measuring position, the measuring device further comprising an aiming member adapted to project a beam onto the moving part , the aiming member preferably being a laser level, the measuring tool being further adapted to cooperate with the sighting member to provide second information representative of a second deviation (E 2 ) between the edge of the platform and the sill in the direction of elevation (Z), the movable part being adapted to form a target capable of cooperating with the sighting member to provide the second piece of information representative of the second deviation (E 2 ). - a support adapted to be installed on the edge of the dock , the support having at least one locating surface for abutting the dock in the transverse direction (Y) and in an elevation direction (Z) substantially normal to the transverse direction (Y); - a movable part mounted on the support and translatable relative to the support in a first direction (A) between a plurality of positions, including a measuring position in which the support is intended to abut the edge of the dock and the movable part is intended to abut the sill of the rail vehicle ; and - an indicator system of the first deviation (E 1 ) adapted to provide first information representative of the first deviation (E 1 ) when the movable part is in the measuring position, the measuring device further comprising an aiming member adapted to project a beam onto the moving part , the aiming member preferably being a laser level, the measuring tool being further adapted to cooperate with the sighting member to provide second information representative of a second deviation (E 2 ) between the edge of the platform and the sill in the direction of elevation (Z), the movable part being adapted to form a target capable of cooperating with the sighting member to provide the second piece of information representative of the second deviation (E 2 ). the measuring device further comprising an aiming member adapted to project a beam onto the moving part , the aiming member preferably being a laser level, the measuring tool being further adapted to cooperate with the sighting member to provide second information representative of a second deviation (E 2 ) between the edge of the platform and the sill in the direction of elevation (Z), the movable part being adapted to form a target capable of cooperating with the sighting member to provide the second piece of information representative of the second deviation (E 2 ). <EOS>