Freight CBM and chargeable weight calculator
Enter each line of a packing list, or import it as a CSV, and get the volume in cubic metres, the volumetric weight and the chargeable weight for air, courier, road or sea LCL. The divisor is shown and editable, every line shows its arithmetic, and a missing weight is reported instead of guessed.
The volume is the start of a quote. Mirage drafts the rest.
Mirage reads incoming freight RFQs, matches them to your rate tables and lane history, and returns the quote. Send us a few of your requests and we send back a plan, no commitment.
Prefer to talk it through? Book a call
The ratio by mode, and where it comes from
- Air freight
- IATA's rule charges on volume when a consignment averages more than 6,000 cm³ per kg, which is 366 in³ per kg or 166 in³ per lb. The cubic volume of all pieces is added up first and divided once, and IATA rounds the chargeable weight up to the next half kilogram. Carriers can quote other ratios for some products: the rate confirmation decides.
- Courier and express
- Express networks commonly use 5,000 cm³ per kg, and US domestic parcel tariffs state their divisor in cubic inches per pound (139 in³/lb works out at about 5,022 cm³ per kg). Your account's service guide decides.
- Road
- No common ratio. Groupage and pallet carriers state their own, often in kg per m³ or per loading metre, and it changes by country and service. Choose "kg per m³" above and type the tariff's figure.
- Sea LCL
- Consolidators' tariffs typically quote a rate per 1,000 kg or per 1 m³, whichever yields more: one "revenue ton" is 1 m³ or 1,000 kg. That is the same arithmetic as a divisor of 1,000 cm³ per kg. Minimum charges and other ratios exist on some lanes.
How it is calculated
volume (cm³) = length × width × height × pieces, dimensions in cm
volume (m³) = volume (cm³) ÷ 1,000,000
volumetric weight (kg) = total volume (cm³) ÷ divisor
chargeable weight = max(total actual weight, total volumetric weight)
Dimensions in mm, m or inches are converted to centimetres first (1 in = 2.54 cm exactly), and pounds to kilograms (1 lb = 0.45359237 kg exactly). The comparison is made once, for the whole consignment, not line by line: a heavy pallet and a light carton shipped together are billed on their combined weight or their combined volume. The sum of per-line maxima is shown as a detail because some people expect it, but it is not what a carrier bills.
Importing a packing list
One line per item size, with a header row or without. Separators: comma, semicolon or tab, detected from the first line. Numbers are read in the page's format (here 1,250.5); in a comma-separated file, write them without a thousands separator or put them in quotes. Empty unit cells mean cm and kg. Up to 500 lines; nothing leaves your browser.
- description
- Free text: carton, pallet, part number.
- qty
- Number of identical pieces. Empty means 1.
- length, width, height
- One piece's outside dimensions, packaging included.
- unit
- cm, mm, m or in.
- weight per piece
- Gross weight of one piece. Leave empty if unknown: the line still counts for volume.
- weight unit
- kg or lb.
- line weight (optional)
- Gross weight of the whole line. Used when weight per piece is empty, checked against it otherwise.
description,qty,length,width,height,unit,weight per piece,weight unit
Pallet A,2,120,80,150,cm,310,kg
Carton B,12,60,40,40,cm,,kg
What the container figure means
The ratio compares the total volume with the nominal inside volume of an example container. It says nothing about loadability: a container is rarely filled to its inside volume, and how much fits depends on the pieces, how they stack, how they are packed and secured, and on weight.
The tool also flags any piece that cannot pass the door or exceeds the inside length in any orientation, and any piece that would only go in turned on its side. It uses Hapag-Lloyd's published example dimensions; containers vary by manufacturer.
Sources
- ASEAN logistics curriculum, chapter 5, Calculation of Air Freight: reproduces IATA TACT rule 3.9.4: 6,000 cm³, 366 in³ per kg, 166 in³ per lb, consignment volume, half-kilogram rounding.
- Shipco Transport, NVOCC tariff rules: rule 3.B: rates per 1,000 kilos or 1 cubic meter, whichever yields the greater revenue.
- Hapag-Lloyd, 20' standard container: inside 5,900 × 2,352 × 2,395 mm, door 2,340 × 2,292 mm, 33.2 m³.
- Hapag-Lloyd, 40' standard container: inside 12,032 × 2,352 × 2,395 mm, 67.7 m³.
- Hapag-Lloyd, 40' high cube container: inside 12,032 × 2,350 × 2,700 mm, door 2,340 × 2,597 mm, 76.3 m³.
FAQ
It depends on the mode, because each mode prices space differently. In sea LCL, 1 m³ is counted as 1,000 kg (one revenue ton). In air freight at IATA's 6,000 cm³ per kg, 1 m³ is 166.67 kg of volumetric weight. At the 5,000 used by many express networks, 1 m³ is 200 kg. You pay on the volumetric figure only when it is higher than the actual weight.
Because carriers bill the consignment. IATA's rule adds up the volume of every piece and divides once, then compares with the total actual weight. Taking the larger of the two piece by piece and adding the results overstates the bill whenever heavy and light pieces travel together.
Yes. Set "Weight is" to "for the whole line", or in a CSV leave "weight per piece" empty and fill "line weight". If both columns are filled, the tool checks that they agree and flags the line if they do not.
Yes, per line. Inches are converted at exactly 2.54 cm and pounds at exactly 0.45359237 kg before anything is added up, so a list that mixes units is still computed once. If your tariff states its divisor in cubic inches per pound, choose that unit for the ratio.
Not necessarily. The figure compares volumes only. Pieces that cannot be stacked or tipped, odd shapes, packaging gaps, load securing and the payload limit all reduce what actually goes in. Use it to choose which container size to ask about, then confirm with your forwarder.
No. It gives the weight a carrier will compare its rates against. The price also depends on the lane, the rate, minimum charges and surcharges.
The dimensions are already on the packing list.
Mirage deploys AI agents that read packing lists and quote requests as they arrive, compute volume and chargeable weight per your carriers' ratios and prepare the quote for your team to check.
See freight RFQ automation