Why 85% volume utilization is often 100% full

Divide your cargo volume by the container volume and you get the number everyone quotes: utilization. A 33 m³ box with 26 m³ of cartons is '79% full', so surely one more order fits. Then the crew closes the doors on a wall of freight and swears there is no room — and they are right.

Volume math assumes cargo is liquid. Real cartons leave gaps: a 60 cm cube in a 100 cm bay strands 40 cm you can never use; freight that can't be stacked wastes the entire column of air above it; boxes that can't be turned kill otherwise perfect rows. What you actually achieve once real boxes are packed — not the volume on paper — is the honest ceiling, and for mixed freight it is typically 80–90% of the theoretical volume.

That gap is where overbooking, rolled cargo, and last-minute second trucks come from. The only way to quote a load you can actually close the doors on is to pack it virtually first, with the same constraints the crew faces: support, stacking flags, orientation.

Our free container calculator runs that exact placement engine on your carton list and shows you the load in 3D — including precisely which cartons do not make it.