How do you calculate chargeable weight for air freight?

Air freight chargeable weight is the greater of the actual gross weight and the volumetric (dimensional) weight. Volumetric weight is length × width × height in centimetres divided by 6000 for each piece — or divided by 166 when working in inches and pounds — then multiplied by the number of pieces. Airlines bill on the higher of gross and volumetric, rounded up to the next 0.5 kg.

What is the difference between volumetric weight and gross weight?

Gross weight is what the cargo physically weighs on a scale. Volumetric weight converts the space it occupies into a weight using the IATA dimensional factor, because a light but bulky shipment costs the airline space, not just payload. Light, bulky cargo is billed on volumetric weight; dense cargo on gross weight. The break-even is 166.67 kg per cubic metre — denser than that bills on gross, lighter bills on volume.

What is the IATA dimensional (DIM) factor?

The IATA standard dimensional factor is 6000 cm³/kg — equivalently 166 in³/lb. It is the volume that airlines treat as equal to one kilogram. Some express and courier services apply a denser 5000 cm³/kg (139 in³/lb) factor, which produces a higher volumetric weight for the same box, so always confirm the factor on your rate.

How do I know if my cargo needs a passenger aircraft belly or a freighter?

As a rule of thumb, a single piece taller than about 160 cm will not fit a standard lower-deck (belly) ULD and needs a widebody lower hold with taller ULDs or a main-deck freighter. Pieces over roughly 300 cm, or very heavy single pieces, need a freighter with heavy or outsized handling. Narrowbody passenger aircraft are bulk-loaded through small doors and take only smaller pieces. Always confirm the exact ULD and door limits for the booked aircraft with your carrier.

What documents does air cargo need, and what changes for dangerous or special cargo?

Every air shipment needs an air waybill (a MAWB, plus a HAWB on consolidations), a commercial invoice, and a packing list. Dangerous goods add a signed Shipper's Declaration under the IATA DGR, with UN number, class, packing group, and passenger-versus-cargo-aircraft quantity limits. Perishables need cool-chain handling and often phytosanitary or health certificates; live animals follow the IATA Live Animals Regulations and CITES for protected species; valuables and human remains carry their own secure-handling and certificate requirements.

Does chargeable weight apply to LCL sea freight?

No — chargeable weight is an air-freight concept. LCL ocean freight is priced on revenue ton (weight or measure), the greater of one tonne or one cubic metre. This calculator is built for air cargo; for LCL, compare CBM against gross tonnes to find the revenue ton.

Free tool

Air Freight Chargeable Weight Calculator

Chargeable weight is the greater of a shipment's actual gross weight and its volumetric weight — length × width × height ÷ 6000 per piece under the IATA dimensional factor. Enter your cargo to get the chargeable weight airlines bill, plus a loadability and document check by cargo type.

DIM factor

Length

Width

Height

Pieces

pcs

Total gross weight

Enter one piece's dimensions and the piece count. Volumetric weight = (L × W × H) ÷ 6000 per piece.

Actual (gross) weight180.0 kg

Volumetric weight320.0 kg

Chargeable weight320.0 kg

Billed on volumetric weight — 1.92 m³ at 94 kg/m³ (break-even 167 kg/m³).

Loadability

Within the standard lower-deck (belly) ULD envelope on most widebody passenger aircraft. Confirm the exact ULD and door limits for the booked flight.

Chargeable weight rounds up to the next 0.5 kg per IATA rule. Loadability is a planning rule of thumb — Zavin advises the exact aircraft, ULD, and documents automatically from your booking.

How air freight chargeable weight is calculated

Airlines sell two things at once: payload and space. So they bill on chargeable weight — the greater of the actual gross weight and the volumetric weight, which converts the space a shipment occupies into a weight:

Volumetric weight = (L × W × H cm) ÷ 6000 · Chargeable = max(gross, volumetric)

The IATA standard dimensional factor is 6000 cm³/kg (equivalently 166 in³/lb). Chargeable weight is rounded up to the next 0.5 kg, and rates are then applied on IATA weight breaks — normal (N), then +45, +100, +300, +500, and +1000 kg — where the per-kilo rate steps down as the shipment gets heavier.

Volumetric vs gross: the break-even density

Whether you pay on gross or volume comes down to density. With the 6000 factor, the break-even is 166.67 kg per cubic metre. Cargo denser than that (machinery, tiles, liquids) bills on gross weight; anything lighter and bulkier (furniture, packaging, apparel) bills on volumetric weight. Knowing which side of 166.67 kg/m³ your cargo sits on tells you whether shaving dimensions or consolidating pieces will actually lower the bill.

Will it fit? Loadability by deck and ULD

Chargeable weight decides the price; dimensions decide whether the cargo flies at all. Cargo loads either into lower-deck (belly) holds under a passenger cabin, or onto the main deck of a freighter. Height is usually the binding constraint:

ULD	Deck	Typical use
LD3 (AKE)	Lower deck (belly)	Half-width container, ~1,588 kg, ~4.5 m³ — widebody passenger & freighter
LD7 / LD11 (ALF/ALP)	Lower deck (belly)	Full-width pallet for widebody lower holds
PMC / PAG (main-deck pallet)	Main deck (freighter)	96 × 125 in pallet; tall pieces up to ~300 cm high
Bulk / loose load	Narrowbody belly	A320 / 737 family — small pieces through a small door only

Rule of thumb: a single piece over ~160 cm tall clears standard lower-deck ULDs only on a widebody hold or a freighter main deck; over ~300 cm or very heavy needs a freighter with heavy/outsized handling. ULD internal dimensions and door openings vary by aircraft and configuration — always confirm with the carrier for the specific flight.

IATA documents & special handling by cargo type

The air waybill, commercial invoice, and packing list are the baseline. Special cargo layers requirements on top — get any of these wrong and the shipment is refused at acceptance:

Cargo type	Code	Key requirements
General cargo	GCR	Air waybill, commercial invoice, packing list.
Dangerous goods	DGR	UN number, class, and packing group; signed Shipper's Declaration; passenger (PAX) vs cargo-aircraft-only (CAO) limits; correct packing, marking, and labelling; DG cut-off.
Perishables	PER	Temperature / cool-chain handling; often phytosanitary or health certificates.
Pharmaceuticals	COL / GDP	Validated cold chain (active or passive); Good Distribution Practice handling.
Live animals	AVI	IATA Live Animals Regulations (LAR); CITES for protected species; approved containers.
Valuables	VAL	Secure handling, value declaration, restricted access.
Human remains	HUM	Death and embalming certificates; approved coffin or urn.
Dry ice	UN 1845	Declared as dangerous goods (Class 9); net quantity shown on the air waybill.

How Zavin automates weight, loadability & documents

This calculator does one shipment at a time. Inside Zavin's operations toolkit, the air-cargo tool runs it automatically: it reads the dimensions and weights straight from the booking email, computes chargeable weight, advises which aircraft and ULD the cargo fits, and flags the IATA documents and handling each cargo type and sub-type needs — so the operator prices and books from correct numbers instead of a re-typed spreadsheet.

See Zavin Run Your Air Freight Explore the Operations Toolkit

Frequently asked questions

How do you calculate chargeable weight for air freight?: Air freight chargeable weight is the greater of the actual gross weight and the volumetric (dimensional) weight. Volumetric weight is length × width × height in centimetres divided by 6000 for each piece — or divided by 166 when working in inches and pounds — then multiplied by the number of pieces. Airlines bill on the higher of gross and volumetric, rounded up to the next 0.5 kg.
What is the difference between volumetric weight and gross weight?: Gross weight is what the cargo physically weighs on a scale. Volumetric weight converts the space it occupies into a weight using the IATA dimensional factor, because a light but bulky shipment costs the airline space, not just payload. Light, bulky cargo is billed on volumetric weight; dense cargo on gross weight. The break-even is 166.67 kg per cubic metre — denser than that bills on gross, lighter bills on volume.
What is the IATA dimensional (DIM) factor?: The IATA standard dimensional factor is 6000 cm³/kg — equivalently 166 in³/lb. It is the volume that airlines treat as equal to one kilogram. Some express and courier services apply a denser 5000 cm³/kg (139 in³/lb) factor, which produces a higher volumetric weight for the same box, so always confirm the factor on your rate.
How do I know if my cargo needs a passenger aircraft belly or a freighter?: As a rule of thumb, a single piece taller than about 160 cm will not fit a standard lower-deck (belly) ULD and needs a widebody lower hold with taller ULDs or a main-deck freighter. Pieces over roughly 300 cm, or very heavy single pieces, need a freighter with heavy or outsized handling. Narrowbody passenger aircraft are bulk-loaded through small doors and take only smaller pieces. Always confirm the exact ULD and door limits for the booked aircraft with your carrier.
What documents does air cargo need, and what changes for dangerous or special cargo?: Every air shipment needs an air waybill (a MAWB, plus a HAWB on consolidations), a commercial invoice, and a packing list. Dangerous goods add a signed Shipper's Declaration under the IATA DGR, with UN number, class, packing group, and passenger-versus-cargo-aircraft quantity limits. Perishables need cool-chain handling and often phytosanitary or health certificates; live animals follow the IATA Live Animals Regulations and CITES for protected species; valuables and human remains carry their own secure-handling and certificate requirements.
Does chargeable weight apply to LCL sea freight?: No — chargeable weight is an air-freight concept. LCL ocean freight is priced on revenue ton (weight or measure), the greater of one tonne or one cubic metre. This calculator is built for air cargo; for LCL, compare CBM against gross tonnes to find the revenue ton.

Last updated: July 2026 | v1.0