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This article was co-authored by Grace Imson, MA and wikiHow staff writer Cheyenne Main. Grace Imson is a math teacher with over 40 years of teaching experience. Grace is currently an instructor of mathematics at the City College of San Francisco, and was previously in the Department of Mathematics at Saint Louis University. She taught mathematics in elementary, middle, high school and college. She received her master’s degree in education, specializing in administration and supervision from Saint Louis University. There are 11 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of all quoted facts and confirming the authority of its sources. This article has been viewed 729,797 times.
Regardless of which postal service you choose, the cost of sending a package will depend on its size. To make sure you are paying the right amount for shipping, it is important to know the exact dimensions of the box you are shipping your item in. Use a ruler or measuring tape to determine the length, width and height of the box. You can then use those measurements to calculate other metrics such as overall size and dimensional weight, which could contribute to the package’s shipping cost.
- Measure the length of the longest side of the package to which the flap is attached. Measure the other side that has the flap to find the width.
- To find out the height of the package, measure the box from top to bottom.
- To get the volume or cubic size of the box, multiply the length, width, and height of the box in inches or centimeters.
Measure the longest side of the package that has the flap to determine the length. Determine the longest side of the package to which the lid is attached. Hold a ruler or tape measure to the edge and read the length of the box from one end to the other. Round your measurement to the nearest 1 in (2.5 cm) or 1⁄2 in (1.3 cm).[1]
- Write down the measurements on a piece of paper so you can refer to them later.
- Many delivery services only handle packages up to a certain size, usually specified in whole inches or centimeters.
- The actual length of your package may vary by 1⁄8 inch (0.32 cm).
Measure the other side with the fold to find the width. The width is the distance from one “wall” of the shortest side of the box to the opposite wall. Stretch a ruler or tape across the package from edge to edge, then round to the nearest 1 in (2.5 cm) or 1⁄2 in (1.3 cm).[2]
- The actual width of your package may vary by 1⁄8 inch (0.32 cm).
Measure the height of the side of the box that is not closed. Measure the standing side of the box that does not have a lid attached to one side to record the height. Round the height of the box to the nearest 1 in (2.5 cm) or 1⁄2 in (1.3 cm).[3]
- The actual height of your package may vary by 1⁄8 inch (0.32 cm).
Advice: If your package is irregularly shaped, measure it the same way you would if it were in a rectangular box, taking the length, width, and height from each end point of the box.
Multiply the length, width, and height of the box to find its volume. Volume is equal to cubic size, which indicates the amount of space inside the box. If you have a package that is 12 inches (30 cm) long, 8 inches (20 cm) wide, and 4 inches (10 cm) high, its volume or cubic size would be 384 cubic inches (6,290 cm3).[4]
- Or if you have a box that is 12 inches (30 cm) long, 3 inches (7.6 cm) wide, and 17.5 inches (44 cm) high, its volume would be 630 cubic inches (10,300 cm3).
Divide the volume by the divisor of the carrier to find its dimensional weight. Many major shipping companies use dimensional (dim) weight to calculate shipping costs.[5]
Dimensional weight is not only based on package size, but also on destination and carrier.- Contact your preferred carrier to find out their specific distributor. Here are the divisors (for imperial measurements) for several common carriers in the US:
- FedEx: For US, Puerto Rico or international shipments, divide the cubic size by 139.[6]
- UPS: Divide the cubic size by 139 for daily prices and 166 for retail prices.[7]
- USPS: If the volume of the package exceeds 1728 cubic inches (28320 cm3), divide the cubic size by 166 and round up to the next whole number.[8]
- For example, if the volume of your box is 384 cubic inches (6,290 cm3) and you are shipping via FedEx (139), its dimensional weight is 2.76 cubic inches (45.2 cm3).
- To find the dimensional weight of an irregularly shaped package, multiply the volume by an adjustment factor of 0.785, then divide the answer by the carrier divisor.[9]
- Keep the dimensional weight accurate to get a rough estimate of box shipping costs – try to avoid rounding.
- Contact your preferred carrier to find out their specific distributor. Here are the divisors (for imperial measurements) for several common carriers in the US:
Weigh your package on a postal scale to determine its actual weight. Place the package on the scale and wait for it to show a reading. Note the weight without rounding up as you will compare it to the dimensional weight of the package to see how much you can expect to pay for shipping.[10]
- You can request a package measurement at the post office if you do not own a postal scale.
Advice: Having your own postal scale can save you valuable time and energy if you make frequent deliveries. It is possible to buy a good postal scale online for as little as $20-$30.
Compare the actual weight of the package with its dimensional weight. If the dimensional weight is greater than the actual weight, you will pay the dimensional weight price. Most carriers charge whichever of the two weights is higher in order to increase their profit per shipment.[11]
- It is important to know the actual weight of your package as well as its dimensional weight because dimensional weight is only an estimate and not a precise measurement.
Double the width and height and add them to find the volume. After finding the length, width and height of the package, multiply the width and height dimensions by 2. Then add the doubled width and doubled height together. The number you get is the circumference of the box.[12]
- If your box is 12 inches (30 cm) long, 4 inches (10 cm) wide, and 6 inches (15 cm) high, doubling the width and height would give you 8 inches (20 cm) and 12 inches (30 cm) .
- When you add 8 inches (20 cm) and 12 inches (30 cm), the circumference is 20 inches (51 cm).
- The term “circumference” refers to the total distance around the thickest part of the box.[13]
This only applies to the area surrounding the shortest side of the package, so the length is not necessary.
- If your box is 12 inches (30 cm) long, 4 inches (10 cm) wide, and 6 inches (15 cm) high, doubling the width and height would give you 8 inches (20 cm) and 12 inches (30 cm) .
Add the combined length and girth to get the total package size. When sending crushed packages, you may be asked for the total package size. To do this, simply add up the length and girth measurements.
- If you add the length of 12 inches (30 cm) to the circumference of 20 inches (51 cm), you get a total size of 32 inches (81 cm).
- If the package you are sending is greater than 105 inches (270 cm) in combined circumference and length, you may be charged an additional special handling fee.[14]
- The largest size for most packages is 130 inches (330 cm). The maximum weight is 70 pounds (32 kg) for international packages and 50 pounds (23 kg) for US ground packages.[15]
Ruler or tape measure
Postal scale (optional)
Categories: How to
Source: HIS Education