Loading Metre (LDM) Calculator

What a loading metre is

A loading metre (LDM) is one metre of trailer floor length across the full width of the trailer. European road carriers sell part loads and groupage this way because floor space, not weight, is what usually runs out first. A standard curtainsider or box semi-trailer is 13.6 m long inside and about 2.4 m wide, so it offers 13.6 LDM, and a pallet that takes up a third of the width over 1.2 m of length uses 0.4 LDM.

This calculator works out the loading metres for each pallet type, allows for stacking, converts the total to a chargeable weight with your carrier's kg-per-LDM rule, and compares the result with the actual weight.

The LDM formula

The per-trailer counts are floor positions, single-stacked, after a small allowance for the bulkhead and doors. Euro pallets reach 33 by loading rows of three lengthwise; the arithmetic alone (13.6 ÷ 0.4) says 34, but that leaves no tolerance at all. *Two US pallets side by side on their 48-inch edge need 2.44 m, so they load two abreast only in trailers wider than the nominal 2.4 m inside (many curtainsiders are 2.45–2.48 m); otherwise they go 40-inch side across and 22 fit.

Worked example: a groupage booking

A shipper books six Euro pallets of 420 kg that cannot be stacked, and four industrial pallets of 300 kg that can go two high.

• Euro pallets: 6 × 0.4 = 2.4 LDM.
• Industrial pallets: 4 pallets two high take 2 floor positions, 2 × 0.5 = 1.0 LDM.
• Total 3.4 LDM, a quarter of a 13.6 m trailer.
• At 1,750 kg per LDM that is 5,950 kg of chargeable weight. The actual weight is 6 × 420 + 4 × 300 = 3,720 kg, so the booking is charged on 5,950 kg.

Make the Euro pallets stackable two high and they take three floor positions instead of six: 1.2 LDM, 2.2 LDM in total and 3,850 kg chargeable, which is now close to the real weight. Stackability is often the single biggest lever on a groupage price.

Mistakes that make part loads expensive

• Booking as stackable when it isn't. If the driver cannot stack the pallets safely, the carrier re-measures and re-invoices at the full floor space.
• Odd widths. A 1.0 × 1.0 m pallet is 0.417 LDM by the formula, but only two fit across a 2.4 m trailer, so each really blocks 0.5 m. The calculator shows the row-based figure when it differs; many carriers bill that way.
• Assuming 1,750 kg everywhere. Carriers use 1,750, 1,850 or 2,000 kg per LDM, and some convert by cubic metre instead. One ratio can change the chargeable weight by 15 %.
• Overhang and loose cartons. A load wider than its pallet is measured at its widest point, and loose freight is measured as the floor it occupies.
• Forgetting the height. LDM ignores height, so a low, heavy pallet and a tall, light one cost the same floor space. Tall freight is a good candidate for a mega trailer's extra internal height.