Carton Packing Calculator: Items per Carton, CBM & Gross Weight
Free carton packing calculator: work out how many products fit in a carton or wooden crate with protection gaps, rotation and stack layers. Get items per carton, cartons required, CBM, net and gross weight, volumetric weight and stacking load, with a 3D packing preview.
Product, Box and Protection Settings
Enter product size, quantity and protective spacing to arrange them inside a carton or wooden crate.
3D Carton Packing Preview
Transparent carton or wooden crate frame with generated product layout.
Packing Results: CBM, Box Count and Gross Weight
Every figure below updates automatically from the packing layout you built above. Use it to fill in a packing list, a proforma invoice, or a freight quote request.
Waiting for the first calculation from the tool above.
Volume Summary Live
Total shipped volume is what a forwarder charges on for LCL sea freight. It is always larger than total product volume because it includes protection gaps and box walls.
Quantity and Weight Summary Live
Gross weight here is product weight only. Add carton tare and inner packaging in the gross weight calculator below for a shipping-document figure.
Packing Calculators
Each calculator starts from the layout above, and every field can be overwritten by hand if you want to test a different scenario.
CBM Calculator
Cubic metres for any box size and quantity.
Carton Quantity Calculator
How many boxes an order needs, and how full the last one is.
Gross Weight Calculator
Net, packaging and gross weight for the packing list.
Volumetric & Chargeable Weight
Air, courier and express freight bill on the greater of actual and volumetric weight.
Stacking Load Estimate
What the bottom box in a stack has to carry.
Oversize & Overweight Check
Compare a finished box against carrier limits before you commit to the box size.
Logistics Unit Converter
Type in either box. Use the arrow button to reverse a pair.
1 CBM = 35.3147 CFT · 1 inch = 2.54 cm · 1 kg = 2.20462 lb · 1 m = 3.28084 ft
Packing Formulas and Definitions
The exact arithmetic behind every number on this page, so you can reproduce or audit the results in a spreadsheet.
Core formulas
CBM = Length (cm) × Width (cm) × Height (cm) ÷ 1,000,000
Packed unit size = Product size + 2 × protection gap on each axis
Items per box = floor(fit on length) × floor(fit on width) × layers
Boxes required = ceil(Total products ÷ Items per box)
Full boxes = Boxes required − 1, if there is a remainder
Last box quantity = Total products mod Items per box (or a full box if 0)
Net weight/box = Product weight × Items per box
Gross weight/box = Net weight + inner packaging + box tare
Volumetric weight = L × W × H (cm) ÷ divisor
Chargeable weight = max(Actual gross weight, Volumetric weight)
Space utilization = Product volume in the box ÷ Internal box volume × 100
Top load estimate = Gross weight per box × (Stack layers − 1)
Terms used on this page
| Term | Meaning |
|---|---|
| CBM | Cubic metre. The standard volume unit for LCL sea freight pricing. |
| CFT | Cubic foot. 1 CBM = 35.3147 CFT. Common in North American quotes. |
| Packed unit | The product plus its protective material (foam, EPE, bubble wrap, dividers). This is what actually occupies space inside the box. |
| Protection gap | Reserved clearance around each product. A 1 cm gap on all sides adds 2 cm to each dimension of the packed unit. |
| Net weight | Product weight only, with no packaging. |
| Gross weight | Net weight plus all packaging, including the box itself. |
| Tare weight | The empty weight of the carton or wooden crate. |
| Volumetric divisor | The number a carrier divides cm³ by to get a billable weight. 6000 is the IATA air freight standard; express couriers commonly use 5000. |
| Chargeable weight | The greater of actual gross weight and volumetric weight. This is what you are billed on. |
| BCT / ECT | Box Compression Test and Edge Crush Test. Lab measures of how much vertical load a corrugated box can take before collapsing. |
Common volumetric divisors
| Divisor | Typical use | 1 CBM bills as |
|---|---|---|
| 5000 | International express couriers | 200 kg |
| 6000 | IATA standard air freight | 167 kg |
| 7000 – 8000 | Consolidator and negotiated air rates | 143 – 125 kg |
| 12000 – 18000 | Some domestic road and parcel tariffs | 83 – 56 kg |
Always confirm the divisor on your own rate sheet. Carriers change it by lane, service level and contract.
How to Calculate Carton Packing in Six Steps
The full workflow, from an empty carton size to a finished packing list you can hand to a supplier.
- Choose a carton or wooden crate size. Pick a standard carton preset or enter a custom carton or wooden crate size in centimetres, plus the reference maximum gross weight per box.
- Enter the product size, quantity and weight. Enter the length, width, height, total order quantity and unit weight of the product. Switch to multiple products if you need mixed packing in one box.
- Set the protection gap. Add the foam, EPE or bubble wrap clearance around each product. This produces the packed unit size, which is what actually occupies space inside the box.
- Read the layout and capacity result. The 3D preview shows the arrangement, and the result panel gives items per box, boxes required, full boxes, last box quantity and space utilization.
- Check CBM, gross weight and carrier limits. Use the calculators below the tool to confirm total CBM, gross weight per box, chargeable weight, stacking load and any oversize or overweight limits.
- Send the boxes to the container planner. Use the transfer button to carry the finished box size, quantity and gross weight into the container loading calculator.
Packing Calculation FAQ
Short answers to the questions that come up most often when sizing cartons and wooden crates for export.
How do you calculate CBM for a carton?
Multiply length by width by height in centimetres, then divide by 1,000,000. A 60 x 40 x 35 cm carton is 60 x 40 x 35 / 1,000,000 = 0.084 CBM. Multiply by the number of cartons for the shipment total.
How many products fit in one carton?
Divide each internal carton dimension by the corresponding packed unit dimension, round each result down to a whole number, then multiply the three results together. Rounding down matters: 60 / 22 is 2.7, but only 2 units actually fit along that axis. The 3D tool on this page tests every rotation and picks the orientation with the highest count.
What is the difference between net weight and gross weight?
Net weight is the product alone. Gross weight adds every gram of packaging: inner bags, foam, dividers, and the empty carton or crate. Customs declarations and bills of lading normally use gross weight, while the commercial invoice often shows both.
What is volumetric weight and when does it apply?
Volumetric weight converts a shipment size into a billable weight, so carriers are not paid nothing for light, bulky freight. It applies to air freight, express courier and many road tariffs. Divide length x width x height in centimetres by the carrier divisor, usually 5000 or 6000. You pay on whichever is greater: actual gross weight or volumetric weight.
Does volumetric weight apply to sea freight?
Not in the same way. FCL sea freight is priced per container, and LCL is priced on whichever is greater between CBM and weight in tonnes, usually with 1 CBM treated as 1000 kg. So for LCL you compare CBM against tonnes rather than using a divisor.
How much protection gap should I allow around a product?
It depends on the product fragility and the transport mode. As a working starting point: 1 to 2 cm for durable consumer goods, 3 to 5 cm of foam for electronics and glass, and more for anything with a projecting or unsupported part. Remember the gap applies to both sides, so a 2 cm gap adds 4 cm to each dimension of the packed unit.
How heavy should one carton be?
Most warehouses and manual handling guidelines cap a single carton at about 20 to 25 kg, with a hard practical ceiling near 30 kg before two-person or mechanical handling is required. Beyond that, use a wooden crate on a pallet instead of a heavier carton.
When should I use a wooden crate instead of a carton?
Use a wooden crate when the piece is heavy (roughly above 50 kg), fragile machinery, irregular in shape, or needs to be strapped and lifted with a forklift. Wooden packaging for export usually needs ISPM 15 heat treatment and stamping, so confirm the destination country requirements before you build.
Why is my box space utilization only 60%?
Utilization is product volume divided by internal box volume. Low figures usually mean the product dimensions and box dimensions are not close to whole-number multiples, so there is dead space along one axis. Try a different carton preset, adjust the protection gap slightly, or change the rotation mode in the tool and watch the utilization figure move.
How many boxes can I safely stack?
Estimate the load on the bottom box as gross weight per box multiplied by the number of layers above it, then compare it against the box compression strength divided by a safety factor. Use roughly 4x for normal ocean freight and 5x to 6x for humid climates or storage over 30 days, because corrugated board loses a large share of its strength in high humidity.
Next Step: Load the Boxes into a Container
Once the box size and box count are settled, move to the container stage to see how many boxes fit in a 20GP, 40GP or 40HQ.
All results on this page are planning estimates based on the dimensions you enter. Confirm final packing, weights and stacking limits with your packaging supplier and freight forwarder before production.