How to Measure a Box

When packing large or oddly shaped items, it’s important to make sure that the box you use is the right size for them.

Too small and you won’t be able to close the box to secure it. Too big and your items will be more likely to move around during transport or storage.

To make sure you use the right box size, it helps to measure your box and compare it to the dimensions of your items.

Fortunately, measuring a box is quick and easy, and all you need is a ruler or tape measure.

Here’s how to do it.

What You Need To Know Before Starting

Before starting, it’s important to know two things.

First, remember that box sizes are always written and read in the following order:

LENGTH x WIDTH x HEIGHT

This is the measurement standard that all box manufacturers and vendors use. For example, a box that’s listed as 305mm x 215mm x 280mm means that it is 305mm long, 215mm wide, and 280mm tall inside.

Second, know that boxes can have two measurements: Interior dimensions and Exterior dimensions.

Interior dimensions refer to the size of the space inside the box where your items will be kept. This is the usable space of the box. Keep in mind that the measurements that box manufacturers and vendors always list on their websites and catalogues are the interior dimensions of the box.

Exterior dimensions, on the other hand, refer to its outside dimensions. These measurements will determine the amount of space it will take up in your truck, room, or storage unit. Because of the thickness of corrugated cardboard, a box’s exterior dimensions will always be bigger than its interior dimensions.

Now that you know these essentials, it’s time to measure your box.

Measuring the Interior Dimensions

With the box flaps opened:

1. Measure the inside LENGTH of the box. This will be the longest side of the box on the open face (the flap opening).

2. Measure the inside WIDTH of the box. This will be the shorter side of the box on the open face.

3. Measure the inside HEIGHT of the box. Also referred to as the depth, the height of the box is the length from the base of the box to the top.

Note down these measurements in Length x Width x Height.

Measuring the Exterior Dimensions

Measure the outside of the box the same way you did with its interior, but this time with the box flaps closed

1. Measure the outside length of the box.
2. Measure the outside width of the box.
3. Measure the outside height of the box.

Make sure you measure to the very tip or edge of each side to get an accurate measurement of its exterior dimensions. Depending on the material used for your box and its design, the outside length, width, and height of your box can differ dramatically from its interior dimensions.

Note down these measurements in Length x Width x Height.

Finding the Right Box Size

And there you go: you now know how big your box is both inside and out. Use this system to find the right-sized box for your items and know how much space it will take after.

Remember that it’s often best to get a box that’s slightly bigger than the size or volume of your items. (But not too big – too much extra space can be just as bad as not having enough space.)

If you have any questions or enquiries, feel free to contact us.