Parcel's weight can be calculated by actual weight or volumetric weight. Actual weight is the weight of the parcel in kilogram(kg). Volumetric weight is calculated based on your parcel dimension. If your parcel is huge, you would need to calculate the volumetric weight using this calculator.
Parcel weight will be determined by either actual or volumetric weight (VW) or whichever is higher. VW also applies if either one dimension is above 30cm. If you're sending big items (either side exceeds 30cm), you will need to calculate both volumetric weight and actual weight, and quote whichever is higher on the website to avoid weight discrepancy. View HERE for more info.