It’s not the weight got by weighing a box on a scale. The volume weight is the space occupied by a box in the carrier. Thus, your price will be based on the volumetric weight of the boxes rather than the actual weight.
To understand better, take a cushion or a teddy bear, weigh on a scale –both are lightweight, but by nature are bulky. Carriers will not charge these commodities as per the weighing scale, as their volumetric weight is often on the higher side.
1) Measure three dimensions of the box (length, width, height) and multiply them.
2) If you have measured the dimensions in centimetres, then attain the result by dividing by 5000 (with EU economy services divide by 4000)
3) When your scale of measurement is in inches, then get the result by dividing by 305 (with EU economy services divide by 245)
4) The outcome of this calculation is the volumetric weight of your box. After comparing the volumetric weight to the actual weight of the box, the courier will take the higher side from the two as chargeable weight (this is also known as billable weight).