Abstract: The invention provides dimensional weighing apparatus (5) that may e.g. be placed transparently between the weighing scales (3) and POS terminal (4) of e.g. a postal outlet so as to provide dimensional weighing of a parcel (2). The apparatus (5) senses the parcel height with a sensor (10), and senses the parcel cross-section with a sensor (11) that obtains data points as the parcel (2) rotates on a turntable (12). A control unit (6) determines the parcel volume from the height and cross-section data, and determines a dimensional weight based on the volume and on a minimum chargeable weight per unit volume. It compares the dimensional weight with the actual weight from the scales (3), and outputs the larger value to the POS terminal (4). Various sensor arrangements and profile analyses are described.