How to Measure A Box

For example a 400 x 300 x 250mm box is a completely different size than a 300 x 250 x 400mm box.

Internal vs External Dimensions

The measurements of a cardboard box always refer to the internal dimensions of the carton (the usable space), not the external dimensions. This is done to ensure a snug and protective fit around your product.

Depending on the grade and fluting of the cardboard, the internal and external dimensions of a box can differ significantly, in some cases even 10mm.

TIP: Remember to leave space for any extra padding you wish to use to protect your product and finger room to place your product/s into the box. For example, if you are using bubble wrap to cushion the item then you should add at least 5mm to each dimension.

Length x Width x Depth

Standard box dimensions are given in the order Length x Width x Height (or Depth).  

Make sure to give the dimensions in this order.

Length: is always the longest horizontal measurement or longest opening dimension (unless the box is square i.e length and width are equal).

Width: is the shortest opening dimension.

Height (sometimes referred to as the "depth”): is the vertical dimension of the box when the opening is facing upwards. It always measures distance between TOP and BOTTOM.