A reefer has the same outside measurements as a dry container: 6.058 m long for a 20ft, 12.192 m for a 40ft, 2.438 m wide, and 2.896 m high for a high cube. Inside, reefer container dimensions are a different story. The refrigeration unit is built into the front wall and sticks out into the cargo space, the walls and roof are insulated, and the floor is a raised ventilation floor. All of that comes out of the internal dimensions, so figures for a dry container will overstate what fits.
The table below gives representative values for the 20ft reefer and the 40ft high cube reefer. Actual units differ by a few centimeters depending on the manufacturer, insulation spec and year of build, and tare weight differs too. The marking on the container door always takes priority over any table. If a piece of cargo comes within about 5 cm of a listed limit, ask the shipping line for the spec of the unit you’ll actually get. For dry container types, see our container dimensions guide; for every type in one sortable table, see container specifications.
Reefer container dimensions: 20ft and 40ft high cube
| Type | Internal L × W × H (cm) | Door opening W × H (cm) | Capacity | Tare weight | Max payload | Max gross |
|---|---|---|---|---|---|---|
| 20ft reefer (20RF) | 542.5 × 228.6 × 226.1 | 229 × 220 | 28.0 m³ | 3,080 kg | 27,400 kg | 30,480 kg |
| 40ft high cube reefer (40RH) | 1,158 × 229 × 250 | 229 × 250 | 67.0 m³ | 4,620 kg | 29,380 kg | 34,000 kg |
Max gross (maximum gross weight) in this table is tare plus payload. Shipping lines publish 30,480 kg for the 20ft reefer (ONE and CMA CGM), though some Hapag-Lloyd series are rated at 32,000 kg. For the 40ft high cube reefer, Hapag-Lloyd, ONE and CMA CGM all list 34,000 kg. Published tares run 2,810–3,010 kg for the 20ft and 4,420–4,700 kg for the 40ft high cube, and nominal capacity runs 28.1–28.6 m³ for the 20ft and 67.5–68 m³ for the 40ft high cube.
In practice, the 40ft reefer you’ll be offered is almost always a high cube. CMA CGM’s reefer fleet is 20ft, 40ft high cube and 45ft pallet-wide units, and ONE offers 20ft and 40ft high cube. A standard-height 40ft reefer does exist as an ISO type (42R1 in Hapag-Lloyd’s code list), but few carriers run them. Going the other way, the two lines we checked (Hapag-Lloyd and CMA CGM) list their 20ft reefers at the standard 8'6" height only. We found no 20ft high cube reefer on offer, which doesn’t mean none exists anywhere.
CMA CGM’s 45ft pallet-wide reefer (2,550 mm wide, built for 32–33 euro pallets) measures 13,280 × 2,440 × 2,582 mm inside, with 83.7 m³ of capacity and an average tare of 6,180 kg.
How much space a reefer loses compared with a dry container
Comparing the reefer values above with our dry container values:
| Comparison | Length | Width | Height | Capacity | Tare weight |
|---|---|---|---|---|---|
| 20ft reefer vs. 20ft dry | −47.5 cm | −6.4 cm | −12.9 cm | 28.0 vs. 33.2 m³ (−16%) | +800 kg |
| 40ft high cube reefer vs. 40ft high cube dry | −45 cm | −6 cm | −20 cm | 67.0 vs. 76.3 m³ (−12%) | +740 kg |
Most of the lost length is the refrigeration unit at the front. Width goes to the insulated side walls, and height goes to the insulated roof and the T-floor. In a 20ft reefer, that adds up to 5.2 m³, or 15.7% of the dry container’s capacity. In a 40ft high cube, it’s 9.3 m³, or 12.2%.
Width is limited by the walls, not the door. The door opening is 229 cm wide on both sizes, the same as or slightly wider than the 228.6 cm and 229 cm inside. Height is another matter on the 20ft reefer: the door opening is 220 cm high against 226.1 cm inside, about 6 cm lower. Anything that goes in on a forklift has to be planned to the door height, not the inside height. On the 40ft high cube, door and inside height are both 250 cm in our values; shipping lines publish door heights of 2,502–2,569 mm.
The max load line and the T-floor
A red max load line is painted on the inside walls of a reefer. It marks the highest point cargo may reach, and it’s there to keep a gap for air to circulate. Don’t load above it.
The line sits below the ceiling by an amount that varies with the shipping line and the unit:
- Hapag-Lloyd 20ft reefers: 2,255–2,267 mm inside height, load line at 2,155–2,184 mm (7' 1"–7' 2"), so about 8–10 cm below the ceiling.
- Hapag-Lloyd 40ft high cube reefers: 2,525–2,540 mm inside height, load line at 2,420–2,425 mm (7' 11¼"–7' 11½"), about 10–12 cm below the ceiling.
- CMA CGM: usable height for cargo is 2,158 mm in the 20ft reefer (2,273 mm inside, about 11.5 cm less) and 2,394 mm in the 40ft high cube reefer (2,557 mm inside, about 16 cm less).
So the height you can actually plan to is lower than the internal height in any table. CMA CGM puts it in volume terms: its 20ft reefer is 28.6 m³ nominal but 27.3 m³ in use, and its 40ft high cube reefer is 68 m³ nominal but 64.9 m³ in use.
The load line matters because of how a reefer moves air. Cold air from the unit is blown along the floor and returns over the top of the cargo. Stack above the line and you block that return path, air circulation suffers, and temperatures become uneven across the load.
The floor is the other half of the airflow. A reefer has a T-floor (T-bar floor): rails with channels between them that carry supply air under the cargo so it can rise up through the load. Two rules follow:
- Don’t block the channels at the end of the T-floor, and don’t load cargo beyond where the T-floor ends.
- Don’t leave floor uncovered. Air takes the easiest route. Open floor lets it bypass the cargo (short-circuiting), and the cargo’s heat doesn’t get carried away. Load as a solid block, cover any gaps with cardboard or similar, and never leave empty floor next to the front wall.
Reefer container weight: tare, payload and VGM
Reefers are heavier than dry containers of the same length. With the values in our tables, a 20ft reefer weighs 800 kg more than a 20ft dry container, and a 40ft high cube reefer 740 kg more than a 40ft high cube dry. Comparing reefer and dry containers from the same shipping line, the difference ranges from 510 kg to 790 kg.
Tare varies within a single shipping line, too. Hapag-Lloyd’s four 20ft reefer series for foodstuffs range from 2,770 to 2,920 kg. Its 40ft high cube reefers range from 4,300 to 4,800 kg, with the controlled atmosphere series at the top end. That’s why you should always take the tare from the door marking on your container rather than from a table.
On the road, extra tare comes straight off your cargo allowance. The truck is held to the same gross weight limit, 80,000 lb for the whole vehicle on US Interstate highways or 40 t for a five- or six-axle combination under EU rules, whether the container is a reefer or a dry container. Every kilogram of added tare is a kilogram less cargo. For how road limits and container ratings interact, see our guide to container weight limits and VGM.
For the Verified Gross Mass (VGM), you either weigh the packed container on calibrated, certified equipment (Method 1), or add up the weight of all cargo, packaging, pallets, dunnage and securing material and add the container’s tare (Method 2). With Method 2, use the tare marked on the container, not a dry-container figure or a table value.
Each container’s own maximum gross weight is on its CSC safety approval plate, the plate required under the International Convention for Safe Containers. The CSC plate shows the maximum operating gross mass but not the tare. The markings on the door show both max gross and tare.
How many pallets fit in a reefer container
Floor counts for a single layer:
| Type | Euro pallet (120 × 80 cm) | UK pallet (120 × 100 cm) |
|---|---|---|
| 20ft reefer | 10 | 9 |
| 40ft high cube reefer | 23 | 20 |
These are hand calculations, not calculator output. Each assumes two rows with the pallets turned different ways. In the 20ft reefer (542.5 × 228.6 cm floor), euro pallets go in one row with the 80 cm side along the length (⌊542.5 ÷ 80⌋ = 6) and a second row with the 120 cm side along the length (⌊542.5 ÷ 120⌋ = 4). That’s 10 pallets, and the two rows take 200 cm of the 228.6 cm width. UK pallets fit 5 in one row (⌊542.5 ÷ 100⌋) and 4 in the other (⌊542.5 ÷ 120⌋), 9 in total across 220 cm. On the 1,158 cm floor of the 40ft high cube reefer, the same layout gives 14 + 9 = 23 euro pallets and 11 + 9 = 20 UK pallets.
You can double stack pallets only if the stack stays below the max load line. That leaves less room than in a 20ft dry container, which is 239 cm high inside against 226.1 cm for the reefer, before the load line takes its share. With a Hapag-Lloyd 20ft reefer’s load line at 2,155–2,184 mm, a stack two high has to stay under about 2.15 m, or roughly 107 cm per loaded pallet including the pallet itself. The general method for pallet counts is in our guide to pallets per container.
Temperature, fresh air and power
Set point range. The set point is the temperature you ask the reefer to hold, and the range depends on the shipping line and the equipment. Hapag-Lloyd lists −40 °C to +30 °C for its 20ft and 40ft high cube reefers, held in outside temperatures up to 50 °C. CMA CGM gives a typical range of −25 °C to +25 °C and asks you to contact a local office for anything outside it. Frozen cargo is generally carried at −20 °C or below, lower for high-fat products, and requirements vary by country.
Pre-cooling. A reefer is built to hold a temperature, not to bring warm cargo down to one. Get the cargo to temperature before it goes in: pre-freeze frozen goods and pre-cool chilled goods.
Fresh air vent. Fresh fruit and vegetables keep breathing after harvest, giving off heat, CO₂ and ethylene and using up oxygen. They need the fresh air vent open to the setting the cargo calls for. For frozen cargo, keep the vent closed; for chilled cargo, set it as required.
Controlled atmosphere. For produce that needs more than ventilation, a controlled atmosphere (CA) reefer uses O₂ and CO₂ sensors and automatic ventilation to manage the air inside. Hapag-Lloyd’s ExtraFresh is one example. It’s separate equipment, and heavier: Hapag-Lloyd’s CA 40ft high cube series have tares of 4,570 and 4,800 kg.
Power. Reefers take power from terminals and ships at 380 V / 50 Hz to 460 V / 60 Hz through a 32 A plug. The plug is a four-pin CEE type (three phases plus earth) as specified in ISO 1496-2 Annex M. For inland moves, a genset (generator set) powers the unit. On board, the reefer is plugged in as soon as it’s loaded and unplugged just before discharge, and the goal throughout is to keep time without power as short as possible.
Pre-trip inspection. Before every shipment, the refrigeration unit goes through a pre-trip inspection (PTI) and maintenance.
Common mistakes when planning a reefer load
Planning from dry container figures. By volume, a 20ft reefer holds about 15.7% less than a 20ft dry (about one box in six) and a 40ft high cube reefer about 12.2% less than its dry counterpart (about one in eight). If your booking is built on dry numbers, part of the load gets left behind.
Loading to the ceiling. The internal height isn’t the planning height. Cargo above the max load line blocks the return air, and the load ends up with uneven temperatures.
Forgetting the 20ft door. The 20ft reefer’s door opening is about 6 cm lower than its inside height. Tall pieces that fit inside may not get through the door on a forklift.
Using a dry-container tare for the VGM. A reefer is several hundred kilograms heavier. Take the tare from the container door, not from a dry spec or an average.
Leaving floor space open. Gaps on the T-floor let the air bypass the cargo. Cover them, and keep the floor at the front wall filled.
Test a reefer load in the calculator
You can open the Container Loading Calculator with reefer dimensions already entered. These links fill in the inside length, width and height, the payload limit and the door opening from the table above:
- Open the 20ft reefer in the Container Loading Calculator
- Open the 40ft high cube reefer in the Container Loading Calculator
Then enter your boxes. The calculator first checks which items fit through the door, then runs a 3D loading plan and shows how many fit and what limits the load: space, weight or the quantity you entered.
The links don’t carry a load line, a tare or a max gross. To stay below the load line, reduce the height yourself by the gap your shipping line specifies, for example 8–10 cm on a Hapag-Lloyd 20ft reefer. The calculator also works out capacity from the dimensions you enter, so it shows 28.04 m³ for the 20ft reefer and 66.30 m³ for the 40ft high cube, not the 67.0 m³ nominal figure in the table.
To total the volume of your shipment first, use the CBM calculator. Its container suggestion covers the four standard dry and high cube types only, not reefers, so compare your total against the reefer figures in the table yourself.
What are the internal dimensions of a 20ft reefer container?
A typical 20ft reefer measures about 542.5 × 228.6 × 226.1 cm inside (L × W × H), with a 229 × 220 cm door opening and a capacity of about 28.0 m³. That’s roughly 47 cm shorter, 6 cm narrower and 13 cm lower than a 20ft dry container. Individual units vary by a few centimeters with the manufacturer and insulation spec, so check the unit you’re given if your cargo is close to a limit.
What are the dimensions of a 40ft reefer container?
40ft reefers are almost always high cube units. A typical 40ft high cube reefer measures about 1,158 × 229 × 250 cm inside, with a 229 × 250 cm door opening and a capacity of about 67.0 m³. Standard-height 40ft reefers exist as an ISO type but are rare in carrier fleets, so if you’re offered one, ask the shipping line for that unit’s spec sheet.
How much does a reefer container weigh?
A typical 20ft reefer has a tare weight of about 3,080 kg and a max gross of 30,480 kg, leaving 27,400 kg of payload. A 40ft high cube reefer weighs about 4,620 kg empty, with a 34,000 kg max gross and 29,380 kg payload. Published tares from shipping lines range from 2,810 to 3,010 kg (20ft) and 4,420 to 4,700 kg (40ft high cube). Reefers are several hundred kilograms heavier than dry containers of the same length. For VGM, use the tare marked on the door of your actual container.
How many pallets fit in a reefer container?
On the floor, in a single layer, a 20ft reefer takes 10 euro pallets (120 × 80 cm) or 9 UK pallets (120 × 100 cm). A 40ft high cube reefer takes 23 euro pallets or 20 UK pallets. These counts mix pallet orientations in two rows. You can only stack pallets two high if the full stack stays below the max load line on the container wall, which leaves less room than in a dry container.
Can I plan a reefer load using dry container dimensions?
No. Insulated walls, the refrigeration unit and the ventilated T-floor take space from the inside, so a 20ft reefer has about 16% less capacity than a 20ft dry container (28.0 vs. 33.2 m³) and a 40ft high cube reefer about 12% less (67.0 vs. 76.3 m³). On top of that, cargo must stay below the max load line. Planning from dry figures means roughly one box in six won’t fit in a 20ft reefer and one in eight in a 40ft high cube reefer.
What temperature range can a reefer container hold?
It depends on the shipping line and the equipment. Hapag-Lloyd lists set points from −40 °C to +30 °C, maintained in outside temperatures up to 50 °C. CMA CGM gives a typical range of −25 °C to +25 °C and asks you to contact a local office for anything outside it. A reefer holds temperature; it isn’t designed to cool cargo down, so frozen goods should be pre-frozen and chilled goods pre-cooled before loading.
What power does a reefer container need?
Reefers run on three-phase power from 380 V at 50 Hz to 460 V at 60 Hz, through a 32 A, four-pin CEE plug (three phases plus earth) as set out in ISO 1496-2 Annex M. Terminals and ships supply this power; for inland haulage, a genset (generator set) powers the unit. The aim is to keep any time without power as short as possible.