A system for measuring dimensions of a freight item comprising: a measuring apparatus comprising (a) an elongate gauge member having a sequence of machine-readable codes visible along its length, each of the machine-readable codes representing a length value corresponding to a position along the gauge member relative to a reference position; and (b) a marker device, movable along the length of the gauge member, for designating a selected position on the gauge member, the marker device comprising a machine-readable reference symbol on an external surface thereof, with the reference symbol being located on the marker device such that in use the reference symbol on the marker device and a subset of the machine-readable codes on the gauge member are simultaneously visible; and a mobile computing device comprising a processor, a camera and a non-transitory, processor-readable storage medium, wherein the non-transitory, processor-readable storage medium comprises programming instructions that, when executed, cause the processor to implement a method comprising steps of: capturing an image of the measuring apparatus, when the camera is pointed by a user at the measuring apparatus, including within the image the machine-readable reference symbol together with a visible subset of the sequence of machine-readable codes; identifying within the image the reference symbol; identifying within the image each of the codes within the visible subset; decoding each of the codes within the visible subset to determine a corresponding length value for each code; determining the highest length value of the visible subset of codes; and outputting the highest length value as a measure of a dimension of the freight item. a measuring apparatus comprising (a) an elongate gauge member having a sequence of machine-readable codes visible along its length, each of the machine-readable codes representing a length value corresponding to a position along the gauge member relative to a reference position; and (b) a marker device, movable along the length of the gauge member, for designating a selected position on the gauge member, the marker device comprising a machine-readable reference symbol on an external surface thereof, with the reference symbol being located on the marker device such that in use the reference symbol on the marker device and a subset of the machine-readable codes on the gauge member are simultaneously visible; and a mobile computing device comprising a processor, a camera and a non-transitory, processor-readable storage medium, wherein the non-transitory, processor-readable storage medium comprises programming instructions that, when executed, cause the processor to implement a method comprising steps of: capturing an image of the measuring apparatus, when the camera is pointed by a user at the measuring apparatus, including within the image the machine-readable reference symbol together with a visible subset of the sequence of machine-readable codes; identifying within the image the reference symbol; identifying within the image each of the codes within the visible subset; decoding each of the codes within the visible subset to determine a corresponding length value for each code; determining the highest length value of the visible subset of codes; and outputting the highest length value as a measure of a dimension of the freight item. capturing an image of the measuring apparatus, when the camera is pointed by a user at the measuring apparatus, including within the image the machine-readable reference symbol together with a visible subset of the sequence of machine-readable codes; identifying within the image the reference symbol; identifying within the image each of the codes within the visible subset; decoding each of the codes within the visible subset to determine a corresponding length value for each code; determining the highest length value of the visible subset of codes; and outputting the highest length value as a measure of a dimension of the freight item.