Shipping Container Dimensions & Weight Limits
20ft, 40ft and 40ft High Cube containers compared - internal dimensions, door openings, tare weight, max payload and CBM capacity, in both metric and imperial units. Plus reefer and open-top variants.
Every ocean FCL quote assumes one of a handful of standard ISO container sizes. The three you meet on 95% of commercial trades are the 20ft general-purpose (20'GP), the 40ft general-purpose (40'GP) and the 40ft high-cube (40'HC). This guide gives you the exact internal dimensions, door openings, tare and payload limits - in metric and imperial - plus the reefer and open-top variants.
20ft, 40ft and 40ft HC - the numbers
External length, width and height are fixed by ISO 668. Internal dimensions vary very slightly by manufacturer (a few millimetres); the values below are typical for the current generation of steel dry-freight boxes.
| Spec | 20' GP | 40' GP | 40' HC |
|---|---|---|---|
| External L x W x H (m) | 6.06 x 2.44 x 2.59 | 12.19 x 2.44 x 2.59 | 12.19 x 2.44 x 2.90 |
| External L x W x H (ft) | 20 x 8 x 8'6" | 40 x 8 x 8'6" | 40 x 8 x 9'6" |
| Internal L x W x H (m) | 5.90 x 2.35 x 2.39 | 12.03 x 2.35 x 2.39 | 12.03 x 2.35 x 2.70 |
| Door opening W x H (m) | 2.34 x 2.28 | 2.34 x 2.28 | 2.34 x 2.58 |
| Cubic capacity (CBM) | 33.2 | 67.7 | 76.4 |
| Cubic capacity (CBF) | 1,172 | 2,390 | 2,700 |
| Tare weight (kg) | 2,300 | 3,750 | 3,900 |
| Max gross (kg) | 30,480 | 32,500 | 32,500 |
| Max payload (kg) | ~28,180 | ~28,750 | ~28,600 |
| Max payload (lb) | ~62,130 | ~63,380 | ~63,050 |
How much does a 20ft container weigh?
A standard 20ft dry-freight container has a tare weight (empty weight) of about 2,300 kg (5,070 lb). Its ISO maximum gross is 30,480 kg (67,200 lb), which leaves roughly 28,180 kg of payload. A 40ft GP weighs about 3,750 kg tare with a similar 32,500 kg max gross, and a 40ft HC is about 3,900 kg tare because of the taller corrugated walls.
The number you actually get to fill is limited by two ceilings: the container's rated payload, and the destination country's road-weight rules. In the EU, GCC and much of Asia, road-legal all-in weight caps a 40ft load at ~26,000 kg gross regardless of what the box could take. Always confirm the road cap with your trucker before committing to a heavy stow.
Payload traps: gross vs payload vs road cap
- Container rating (max gross): the ISO/CSC plate number - box plus contents. Rarely the binding limit for cargo.
- Payload: max gross minus tare. This is what shipping lines quote when they say "28 tonnes".
- SOLAS VGM: Verified Gross Mass. Since 2016 the shipper must declare the box's certified weight (tare + payload) to the line before loading. Wrong VGM = short-shipment.
- Road cap: destination truck-axle rules. Often the real ceiling. India, EU and GCC lanes commonly cap 40ft loads at ~26 t all-in.
High-cube (40'HC) vs 40ft GP - when the foot matters
The 40ft high-cube is one foot (30 cm) taller externally, giving 31 cm of extra usable headroom and roughly +9 CBM. That matters for lightweight, high-volume cargo - insulation, foam-filled goods, tall equipment, textiles. It doesn't help dense cargo, since payload is unchanged.
Watch two constraints: the door opening on a 40'HC is 2.58 m high (vs 2.28 m on a GP), so extra-tall items need to enter through a HC specifically; and some tunnels, rail routes and warehouses have clearance issues with 9'6" boxes.
Reefer, open-top and flat-rack variants
| Type | Internal CBM (40ft) | Typical payload (kg) | When to use |
|---|---|---|---|
| Reefer (40' RH) | ~59 | ~27,700 | Temperature-controlled: perishables, pharma, chemicals. |
| Open-top | ~66 | ~26,500 | Over-height cargo loaded from above - machinery, glass. |
| Flat-rack | n/a | ~40,000+ | Out-of-gauge, heavy-lift, project cargo. Priced OOG. |
Using the CBM Calculator
Enter each unique carton size on the CBM Calculator to get total volume, then read the container-utilisation gauge. It compares your stow to the 33 / 68 / 76 CBM benchmarks above and warns when you're above 90% usable capacity (the practical break-point for irregular stowage).
Frequently asked questions
How many CBM fit in a 20ft container?#
Nominal capacity is 33.2 CBM. In practice, plan for 28-30 CBM of stowed cargo because of pallet gaps, dunnage and irregular carton sizes.
How many CBM fit in a 40ft HC container?#
Nominal capacity is 76.4 CBM and a realistic stow is 66-70 CBM.
How much can a 40ft container carry?#
Rated payload is about 28,750 kg (63,380 lb). Road rules at destination usually cut this to ~26,000 kg all-in.
What is the door opening on a 40ft high-cube?#
2.34 m wide x 2.58 m high (7'8" x 8'6"). The extra headroom vs a standard 40'GP is 30 cm.