Girth and Volumemetric Weight Calculator. With our Girth and Volumemetric Weight Calculator you will find out easily if your parcel has the correct size for sending with DPD. Maximum restrictions of your parcel: weight: up to 31.5 kg the combined dimensions (longest side + circumference): 300 cm length (of the longest side): 175 cm. Girth The DPD Girth Calculator will help you find out quickly and simply if your parcel is within the limit for combined dimensions (girth). Volumetric weight The charge for air freight is based on the parcel's volumetric weight, if this is greater than the actual weight in kg. The volumetric weight indicates how much space a parcel takes up in relation to its weight, and is calculated on the basis of the TACT rules operated by IATA (International Air Transport Association) using the following formula: Length x width x height in cm / 6.000 The volumetric weight applies both to worldwide DPD CLASSIC parcels and to international DPD EXPRESS parcels.