Sea freight calculation system for Garments

Though almost garment orders are placed by buyers on FOB (Free On Board) basis, the buyers to pay freight at the shipping destination, it is still necessary for the agent to know how to calculate sea freight and air freight the merchandise costs per Doz. If you are required to sell on CIF (Cost Insurance & Freight) basis, (the shipper or agency to prepay freight at the shipping port) you will need to calculate the freight accurately for your own costing. There are two systems use for calculating freight cost. They are-
  1. Sea Freight
  2. Air Freight
Sea freight:
Sea freight is generally varied based on volume how much per CBM (Cubic meter) very rarely by weight as “density cargo”. In fact, ANRRA (Asia North American Eastbound Rate Agreement) has designed the freight tariff based on the usual value of the type of goods, then the usual weight of them, taking into consideration that for low value merchandise they should give a low freight rate in order to make it possible for the importers to buy goods overseas. However, for high value merchandise, they should charge a high freight rate as it is believed that the buyer can afford to pay more on freight. They have designed the freight tariff in such a way that everybody can do business and there is sufficient profit for the shipping lines. The following is an example to show you the idea:

XYZ Furniture: (Low value goods)
USD 2975.00 for a 40 feet container to East Coast (USA)
Garments (not silk) (Medium value goods)
USD 5295.00 for a 40 feet container to East coast (USA)
Silk Garments (High value goods)
USD 9355.00 for a 40 feet container to East coast (USA)
From the above you will see that for the same 40 feet container the shipping line change very different rates.

Nowadays, it is very common to ship goods by containers and pay the freight for the whole container, even if you sometime do not have the exact volume of merchandise to fill up the whole container. The reason of this is:

Suppose, the shipping line charges US 160 per CBM if you ship goods by the CBM as loose cargo. But, if you ship goods by the container, they charge you about US 350 per 40 feet container (these are approximate rate for shipment from the South East to USA port, but they vary from each of the South East countries and East of West coasts of the United States). However, the above example can give you the general relationship between the rates of loose cargo, 20 feet and 40 feet containers, the following will show this point more clearly:

Note: Figures used in example are not the exact freight rates as they change from time to time, but this is the concept commonly used.

  1. A 20 feet container has the following inside measurement:

Length: 228” x Width: 84” x Height: 94”
228” x 84” x 94” by multiplying 2.54 (as we know 1” = 2.54 cm)
579.12 cm X 213.36 cm X 238.76 cm by dividing 100 (we know 1m = 100 cm)
5.7912 m X 2.1336 m X 2.3876 m = 29.50 CBMS

If you want to more about CBM calculation, then check the below article;

However, a 20 feet container has a capacity of 29.5 CBM, but when you ship goods packed in cartons or wooden crates, it can only hold about 27 CBM as there will be gaps or spaces wasted. If the rate of a 20 feet container is $3700, then your average rate per CBM is about $137 (Total container cost / Maximum hold CBM in container = $3700 / 27). A 20 feet container which means 20’ x 7’ x 8’ but above is the inside dimension. 

  1. A 40 feet container has the following inside measurements:

Length: 474” x Width: 84” x Height: 94”
474” x 84” x 94” by multiplying 2.54 (as we know 1” = 2.54 cm)
1203.96cm X 213.36cm X 238.76cm by dividing 100 (we know 1m = 100 cm)
12.0396m X 2.1336m X 2.3876m = 61.33 CBMS

40 feet container which means 40’ x 7’ x 8’, but above is the inside dimension
Therefore, a 40 feet container cartons or wooden creates, it will hold only about 54 CBM. If the rate of the 40 feet container is $5500 then the average rate per CBM is about $102 (Total container cost / Maximum hold CBM in container = $5500 / 54).

It is noted that there is a bigger container than the 40 feet high cube. The inside measurements are:
Length: 474” x Width: 84” x Height: 106” (12” higher)
474” x 84” x 106” by multiplying 2.54 (as we know 1” = 2.54cm)
1203.96cm X 213.36cm X 269.24cm by dividing 100 (1m = 100cm)
12.0396m X 2.1336m X 2.6924m = 69.16 CBMS

40 feet Hi-cube container which means 40’ x 7’ x 9,’ but above is inside dimension.
A 40 feet Hi-cube container is about 12% higher than a 40 feet regular container, and the cost of a 40 feet Hi-cube is about 10 to 12% higher, so the rate per CBM is about the same. There is very little advantage in using a 40 feet Hi-cube as the rate per CBM is concerned. However, there is great advantage when you have the amount of cargo which exceeds the capacity of a 40 feet container only by 5 to 8 CBM.

  1. If you ship goods as loose cargo, the rate is about $160 / CBM:

From the above you will see that it is most convenient to use 40 feet containers if at all possible. However, it is not always possible for the buyers to buy goods with the quantity adjusted to fill the containers. But if the quantity ordered is so big that it take a few 40 feet containers to ship at different time, then the shipper should plan the shipments carefully so that the right amount of goods is shipped each time to fill a 40 feet container, because the saving in using 40 feet container is so big that it is worth your time and effort to work to achieve it for your buyer.

Example: one Doz. of Men’s stand up collar shirt is about 0.037 CBM.
  1. If you ship this shirt as loose cargo,
0.037 x 160 = $ 5.92/Doz. sea freight
2. If you ship this shirt in a 20 feet container (full)
0.037 x 137 = $ 5.069 / Doz. sea freight
3. if you ship this shirt in a 40 feet container, or a 40 feet Hi-cubic container (full)
0.037 x 102 = $ 3.774 / Doz. sea freight

It is very clear to the above, the good pain of shipping can save your customer a great deal of money.

As most shippers are shipping goods by the container, we may form an opinion that as long as we pay for the whole container we may fill up the container regardless of the weight of the merchandise. However, this is not true, the usual weight limits of the containers are as follows:
  • 20 feet container weight limit: 16,300 kg
  • 40 feet container weight limit: 19,500 kg
Actually the weight mentioned above are weight limits as guidelines for you only. The real limits are the following:
  • 20 feet container 18148 kg including the weight of the container
  • 40 or 45 feet container 25400 kg including the weight of the container
The following are the weights of the containers:
  • 20 feet steel: 1960 to 2350 kg
  • 40 feet steel: 3390 to 4190 kg
  • 40 feet aluminum: 2450 to 3050 kg
  • 45 feet aluminum / steel: 3925 to 4500 kg
Goods like ingot and dry cell batteries can easily exceed the limits. When you ship this type of goods, you may fill the container half and reach the weight limit. For your information, the weight limits are set not so much for the capacity of the ship, it is for the loading and unloading equipment, and the road safety regulations (bridges also) when the container gets ashore. If you ship very heavy goods as loose cargo because the size of the shipment is very small, the shipping line will charge you by weight or by volume whichever is higher.