How full are ocean containers, really?

Cargo got lighter

The clearest change is in what went into the boxes. In 2020, 43.4% of shipments carried light cargo, under 150 kg per cubic meter. By 2022-2023 it was 69.6%, and the median density fell from 161 to 116 kg per cubic meter. Light cargo fills a container's space long before it reaches the weight limit, so for most of these importers, volume sets the cost.

Fill rates themselves barely moved: the median shipment used 82% to 83% of its containers' nominal volume in every period. Nominal volume can't be reached in practice, because cartons and pallets leave gaps, so a well-loaded box typically lands around 85% to 90% on this measure.

What it means for importers

• Light cargo: you pay for space. High cube and 45-foot containers lower the cost per cubic meter, and tighter cartons or floor loading instead of pallets fit more cargo into each box.
• Dense cargo such as tile, stone or machinery hits the weight limit first, and may draw overweight fees on US roads. A 20-foot box is often the better fit.
• Half-empty boxes are usually a timing decision: shipping before an order is complete. Compare the cost against LCL or waiting for the next order.

How this was measured

Fill is the declared cargo volume on each shipment's origin pre-alert divided by the nominal internal volume of its containers: 20' 33 m³, 40' 67 m³, 40HQ' 76 m³, 45' 86 m³, full-container-load shipments only, one record per booking. No importer carries more than 25% of the weight behind any figure, and each period draws on at least 10 importers.

• 90% of the shipments loaded at Yantian, and all came through one origin agent to one forwarder, bound for US and Canadian ports. This describes that trade flow, not the global market.
• Container capacities are nominal internal volumes we assume (20' 33, 40' 67, 40HQ 76, 45' 86 CBM). Usable volume is lower, so 100% is not reachable in practice.
• CBM and weight are the shipper's declared figures on the pre-alert, not measurements.
• A shipment with several containers is measured as one fill rate across its whole box mix.
• Full-container-load shipments only. LCL, records with no equipment or no CBM, and utilisation above 115% (likely a parse or LCL error) are excluded.
• No importer carries more than 25% of the weight behind any figure; pre-alerts that cannot be tied to one importer are excluded.
• Confidence intervals treat shipments as independent. Shipments from one importer tend to load alike, so the true uncertainty is wider, most of all for the under-half-full share, which comes from a handful of importers.
• Historic: the pre-alert feed stopped in November 2023.