How to Calculate Volumetric Weight? Or the different possibilities of transport tariffs…

Freight Pricing Basics: Weight, Volume Weight, and Capacity Units

Transport pricing is driven by a simple constraint: capacity is limited (space and weight). Carriers therefore charge based on either:

• actual gross weight, or
• volume/chargeable weight (a conversion of space into an equivalent weight), or
• capacity units (loading meters, full truck, trailer-on-rail, full container).

The commercial rule is consistent across modes: you pay for the limiting factor—weight or space.

Lorry transport (road freight)

1) Pricing per 100 kg

The rate is quoted per 100 kg of either:

• the actual gross weight, or
• the chargeable weight (if volumetric rules apply).

This method usually rounds up to the next full 100 kg.

2) Pricing per loading meter (LDM)

A loading meter measures how much floor length your shipment occupies on the truck.

Typical reference dimensions:

• Inside truck width: ~ 2.44 m
• Inside truck height: ~ 2.40 m

So 1 LDM ≈ 2.44 m × 1.00 m of floor space, and the theoretical cubic capacity is about 5.8 m³ (height × width × 1 meter length). In reality, usable volume depends on stackability and securing constraints.

Business translation: LDM pricing is similar to renting floor space. Long, non-stackable cargo is expensive even if it is light.

3) Rail “motorcar” / trailer-on-rail (combined transport)

Pricing can be based on renting a complete transport unit on a train, such as:

• a truck unit on rail (e.g., ~35 m³), or
• a trailer on rail (e.g., ~51 m³),
  within legal weight/size limits.

Business translation: you pay for the unit, not per kg—useful when you can fill the asset predictably.

4) Full truck / full lorry (FTL)

A flat price for the use of a full truck (or a combined transport unit with trailer). Best used when:

• volumes justify full capacity,
• cargo requires segregation/security, or
• delivery windows require direct routing.

Transport by plane (air freight)

Airfreight is quoted using chargeable weight, based on whichever is higher:

• actual gross weight, or
• volumetric weight.

A common volumetric rule is:

• 1 m³ = 167 kg
• Equivalent formula: (L × W × H in cm) / 6000 = volumetric kg

Air volumetric weight formula

Length (cm) × Width (cm) × Height (cm) ÷ 6000 = volumetric weight (kg)

Example 1

One crate: 50 × 50 × 50 cm, actual weight 80 kg

• Volume: 50 × 50 × 50 = 125,000 cm³
• Volumetric weight: 125,000 ÷ 6000 = 20.83 kg
• Chargeable weight = max(80, 20.83) → 80 kg

Example 2

Eight identical boxes, each 60 × 40 × 20 cm, total actual weight 45 kg

• Total volume: 8 × (60 × 40 × 20) = 8 × 48,000 = 384,000 cm³
• Volumetric weight: 384,000 ÷ 6000 = 64 kg
• Chargeable weight = max(45, 64) → 64 kg

Business implication: light, bulky freight is penalized in air because space is scarce.

Transport by ship (ocean freight)

For ocean freight (especially LCL / breakbulk), pricing often uses a weight/measurement rate:

• 1 m³ = 1,000 kg (the “1:1” rule)

So the charge basis becomes:

• W/M (weight or measurement): you pay the higher of weight (in metric tons) or volume (in cubic meters).

Business implication: heavy dense cargo pays by weight; light bulky cargo pays by volume.

Why “volume weight” exists (the anvil vs feathers problem)

Two shipments can weigh the same but consume radically different space.

A 500 kg anvil and 500 kg of feather duvets weigh the same, but the duvets occupy far more volume. Without volumetric pricing, carriers would lose money on bulky shipments that block capacity.

That is why the industry uses dimensional (volumetric) weight to convert space into an equivalent “freight weight.”

General volumetric conversion (cross-mode logic)

A practical generic model is:

Volume weight (kg) = (Length × Width × Height in m³) ÷ factor

Example factors sometimes used:

• Ship: 0.001
• Lorry: 0.003
• Plane: 0.006

Note: factors and divisor rules vary by carrier, lane, and product. Always confirm the applicable factor in the tariff or quotation.

Road example (truck)

Case: 80 × 120 × 200 cm = 0.80 × 1.20 × 2.00 m

• Volume: 0.80 × 1.20 × 2.00 = 1.92 m³
• Using a road factor of 0.003: 1.92 ÷ 0.003 = 640 kg
• Chargeable weight = 640 kg (if the actual weight is lower)

Practical takeaways

• Always provide accurate dimensions + weight; pricing errors come from bad data.
• Identify whether your shipment is dense (weight-driven) or bulky (space-driven).
• For bulky cargo, focus on: stackability, compression, packaging optimization, and consolidation.
• Require quotes to state explicitly: the volumetric rule/divisor, rounding method, and any minimum charges.