International express companies are mainly charged according to weight. Generally, when the forwarder gives you a quotation, he will quote you a unit price such as 20/KG, and then multiply it by your billing weight, which is your freight. If it is a declaration document, it will have an additional customs declaration fee of 150 yuan.
However, as regards the billing weight, we may not understand it very well. The billing weight is not necessarily the gross weight of the goods. Because some of the goods are too big and light, if they are charged according to the gross weight, it is not very cost-effective for the shipping company. Therefore, an international definition of the volume weight (bubble weight) and the calculation of bubble weight is given. The way is long * wide * high / 5000 cm, and some channels will be long * wide * high / 6000 cm, and then compare with gross weight, which one is charged according to which one.
For example, if you have a ticket, the actual volume of 15KG gross weight is 50*50*50cm, then the volume weight of the ticket is: 50*50*50/5000=25KGS. The billing weight of the ticket is 25KG, not 15KG gross weight.