Shipping & logistics
Estimate carton capacity for a standard 20-foot container.
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20ft container calculator guide
A 20ft container calculator answers the first question an importer asks when an order gets big enough to consider FCL: how many of my cartons fit in one box? Enter the outer carton length, width, and height in centimetres. The tool converts the carton to cubic metres, divides a fixed 33 m³ of internal volume by that figure, applies an 85% loading factor for the gaps that real stacking leaves, and rounds down. A standard 20ft general-purpose container is about 5.9 m long, 2.35 m wide, and 2.39 m high inside, with a door opening around 2.34 × 2.28 m, and it is usually rated for a 30,480 kg maximum gross mass. This is a volume estimate for uniform cartons stacked loose; palletised cargo, tall or fragile cartons, and heavy goods that hit the payload limit will all reduce the real count. Use it to size an order and to check a supplier’s loading plan.
Carton volume (m³) = length (cm) × width (cm) × height (cm) ÷ 1,000,000. Cartons = floor(33 m³ ÷ carton volume × 0.85).
Worked example: master cartons of 40 cm × 30 cm × 25 cm have a volume of 40 × 30 × 25 ÷ 1,000,000 = 0.03 m³ each. Dividing the 20ft internal volume by the carton gives 33 ÷ 0.03 = 1,100 cartons if every cubic centimetre were used. Applying the 85% loading factor gives 1,100 × 0.85 = 935. If each carton weighs 20 kg, the load is 935 × 20 = 18,700 kg, comfortably under the payload of about 28 t. The calculator displays 935 cartons.
Carton dimensions are centimetres; the container volume (33 m³) and the 85% factor are fixed. For inch measurements multiply by 2.54 first. The carton volume row is shown to three decimals, so a carton smaller than 0.0005 m³ displays as 0.001. If you need a different container size, loading factor, or a carton volume you already know, use the container capacity calculator instead.
Carriers bill on whichever is greater, actual weight or volumetric weight, so treat this result as the number to compare against your carrier's own quote. Divisors, rounding rules, and surcharges differ between carriers and between domestic and international services, and they change with contract terms. Confirm the current rules for your account before you price a shipment. On this page the figure rests entirely on carton length, carton width, carton height, market / jurisdiction, effective date, data source, update owner and review date, so start there if the 20ft container calculator returns something you did not expect.
Good to know: the estimate assumes cartons are hand-stacked floor to ceiling. If the supplier ships on pallets, count pallets instead: a 20ft holds 10 EUR pallets or 9–10 US 48 × 40 in pallets in a single layer. Check the payload before the volume: 935 cartons at 35 kg would be 32.7 t, above the container rating. Cartons taller than the 2.28 m door opening, or a column of cartons that does not fit under the 2.39 m roof, also lower the count.
Shipping results depend on carrier, service, route, divisor, rounding, surcharges, and contract terms. Confirm the current carrier rule before buying a label or quoting a customer.
Sources
How it works
Estimate carton capacity for a standard 20-foot container. This tool explains the calculation so you can adjust the assumptions to match your situation.
Worked example
With Carton length = 40 cm · Carton width = 30 cm · Carton height = 25 cm → 935 cartons (practical volume estimate). Change an input above and this example updates with your numbers.
Common questions
Divide 33 m³ by the carton volume in cubic metres and multiply by about 0.85. For a 40 × 30 × 25 cm carton (0.03 m³) that is 33 ÷ 0.03 × 0.85 = 935 cartons. Larger cartons, pallets, or heavy goods reduce the number.
A standard 20ft dry container is about 5.898 m long, 2.352 m wide, and 2.393 m high inside, giving roughly 33.2 m³. The door opening is about 2.34 m wide and 2.28 m high. Exact figures vary slightly by manufacturer.
Most 20ft containers are rated for a 30,480 kg maximum gross mass under ISO 668. With a tare of about 2,300 kg the payload is roughly 28,000 kg, but road and rail limits in many countries restrict the practical load to around 20–24 t.
Ten EUR pallets (1,200 × 800 mm) or nine to ten US 48 × 40 in pallets fit in a single layer on the 5.9 × 2.35 m floor. Double stacking is possible only if the loaded pallets are under about 1.15 m tall and can bear the weight.
LCL is priced per cubic metre plus fixed handling fees, so once a shipment reaches roughly 13–15 m³ a 20ft FCL is often cheaper and faster, with less handling. Compare a real FCL quote against the LCL rate times your CBM.