We’ve pre-loaded the dimensions of popular cases suitable for shipping, and you can select them when booking. For all boxes or cases not on our list, use a tape measure to determine the following dimensions for your shipment: Length, Width and Height. Length is always the longest side of box or case; Height is the second longest, and Width is the dimension that’s left over. Always round up any Length, Width or Height measurement to the next unit. For example, a measurement of 12.25 inches must be entered as 13 inches, and a measurement of 13.7 cm must be entered as 14 cm.