Ocean LCL is sold by the revenue ton, written R/T or W/M — "weight or measure". One R/T is the greater of one cubic metre and one metric tonne, so the pivot sits at 1000 kg per cubic metre. Below that density the tape measure is billing; above it the scale is. Most general cargo is far below 1000, which is why LCL quotes are usually "per cbm" in conversation even though the tariff says W/M.
The same R/T multiplies every line of the quote, not just the freight: origin CFS, destination CFS, and most per-unit surcharges all ride on it. Getting the R/T wrong by half a cube therefore does not lose you one rate times half a cube — it loses you the whole per-unit column times half a cube.
And the measurement that counts is the CFS's, not the packing list's. Pallets add height, overhang gets squared off, and an awkward crate is measured at its extremes. Quote off the shipper's numbers, collect off the warehouse's, and the difference is yours to explain.
Weight or measure, whichever is greater — the rate applies per revenue ton, where one R/T is the higher of one metric tonne and one cubic metre. "US$52 W/M" means 52 dollars per R/T. It is the ocean cousin of air's chargeable weight, with the pivot at 1000 kg/cbm instead of 167.
The minimum. Almost every LCL tariff bills at least one revenue ton regardless of size, because the fixed work — documentation, handling, manifesting — does not shrink with the cargo. Below roughly half a cube, compare a courier or air: the sea minimum plus two CFS charges often exceeds the airline's minimum on small light shipments, and takes three weeks longer to do it.
Revenue ton and freight ton mean the same thing in modern LCL practice — the W/M billing unit. A metric tonne is only mass, and it is just one side of the comparison. Historic terms like the measurement ton of 40 cubic feet survive in some trades and older tariffs, which is one more reason to read the definition line on the tariff rather than assume.
Sometimes the opposite of what people expect. At 1000 kg/cbm and above you pay by the tonne, so 3 cbm of steel fittings at 4,000 kg bills as 4 R/T — a third more than its volume. That is precisely the cargo a co-loader loves, because it fills their weight allowance without eating space; if you ship dense cargo regularly, that is negotiating leverage on the W/M rate, and at real volume it is the argument for your own box.
Cargo-Stack reads the enquiry, prices it against your own rates, and drafts the quote — with this arithmetic underneath it. Same maths, no retyping.
Try it on a real enquiry