# CONT24 Container Knowledge Base (full)

Standard ISO 668 / ISO 1496 series specifications. Individual units vary slightly by manufacturer; always confirm against the unit's CSC plate.
Source: https://cont24.com — free to cite with a link.

## Container specifications

### 10ft Standard (ISO 12G1)
External: 9' 10" × 8' 0" × 8' 6" (2.991 × 2.438 × 2.591 m)
Internal: 9' 2" × 7' 8" × 7' 10"
Door: 7' 8" × 7' 6"
Tare 2870 lb (1300 kg) · Max payload 19530 lb (8860 kg) · Max gross 22400 lb (10160 kg)
Capacity 563 cu ft (15.9 cbm) · Floor 70 sq ft · Pallets 4 GMA / 5 Euro
US price 2026: used $1500–2500, new (one-trip) $3000–4500
Best for: Tight sites, kiosks, pump rooms, small storage — the only ISO box that fits a standard parking space.
Note: Most 10-footers are not built new — they are cut down from damaged 20ft or 40ft units by depot fabricators.

### 20ft Standard (ISO 22G1)
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: 19' 4" × 7' 8" × 7' 10"
Door: 7' 8" × 7' 6"
Tare 4850 lb (2200 kg) · Max payload 62350 lb (28280 kg) · Max gross 67200 lb (30480 kg)
Capacity 1172 cu ft (33.2 cbm) · Floor 150 sq ft · Pallets 10 GMA / 11 Euro
US price 2026: used $1500–3000, new (one-trip) $2500–5500
Best for: The world's default unit of cargo — and the sweet spot for backyard storage, workshops and single-room conversions.
Note: The 'TEU' (twenty-foot equivalent unit) that measures every port and container ship on Earth is literally this box.

### 20ft High Cube (ISO 25G1)
External: 20' 0" × 8' 0" × 9' 6" (6.058 × 2.438 × 2.896 m)
Internal: 19' 4" × 7' 8" × 8' 10"
Door: 7' 8" × 8' 6"
Tare 5070 lb (2300 kg) · Max payload 62130 lb (28180 kg) · Max gross 67200 lb (30480 kg)
Capacity 1320 cu ft (37.4 cbm) · Floor 150 sq ft · Pallets 10 GMA / 11 Euro
US price 2026: used $2200–3800, new (one-trip) $3500–6000
Best for: A rare box worth hunting for: the extra foot of ceiling makes a 20ft conversion feel like a room, not a corridor.
Note: 20ft high cubes are scarce — under 1% of the global fleet — because ocean carriers get no stacking advantage from them.

### 40ft Standard (ISO 42G1)
External: 40' 0" × 8' 0" × 8' 6" (12.192 × 2.438 × 2.591 m)
Internal: 39' 6" × 7' 8" × 7' 10"
Door: 7' 8" × 7' 6"
Tare 8000 lb (3630 kg) · Max payload 59200 lb (26850 kg) · Max gross 67200 lb (30480 kg)
Capacity 2390 cu ft (67.7 cbm) · Floor 300 sq ft · Pallets 21 GMA / 25 Euro
US price 2026: used $2000–4500, new (one-trip) $3500–6500
Best for: Twice the floor of a 20ft for barely more money — the best dollars-per-square-foot box on the market.
Note: A 40ft container costs roughly 1.3× a 20ft to buy but gives 2× the space — shipping lines price the steel, not the volume.

### 40ft High Cube (ISO 45G1)
External: 40' 0" × 8' 0" × 9' 6" (12.192 × 2.438 × 2.896 m)
Internal: 39' 6" × 7' 8" × 8' 10"
Door: 7' 8" × 8' 6"
Tare 8750 lb (3970 kg) · Max payload 58450 lb (26510 kg) · Max gross 67200 lb (30480 kg)
Capacity 2694 cu ft (76.3 cbm) · Floor 300 sq ft · Pallets 21 GMA / 25 Euro
US price 2026: used $2500–5000, new (one-trip) $4000–7000
Best for: The container-home builder's standard: after insulation and flooring you still keep an 8ft ceiling.
Note: High cubes overtook standard 40-footers in new production years ago — most 40ft boxes built today are 9'6" tall.

### 45ft High Cube (ISO L5G1)
External: 45' 0" × 8' 0" × 9' 6" (13.716 × 2.438 × 2.896 m)
Internal: 44' 5" × 7' 8" × 8' 10"
Door: 7' 8" × 8' 6"
Tare 10360 lb (4700 kg) · Max payload 56840 lb (25780 kg) · Max gross 67200 lb (30480 kg)
Capacity 3040 cu ft (86 cbm) · Floor 340 sq ft · Pallets 24 GMA / 27 Euro
US price 2026: used $3000–5500, new (one-trip) $5000–8000
Best for: Five bonus feet over a 40ft — popular for European intermodal and roomy single-box homes.
Note: The 45ft box hangs over a standard 40ft ship slot on castings set at 40ft spacing — the overhang is engineered in.

### 48ft Domestic (ISO domestic (AAR))
External: 48' 0" × 8' 6" × 9' 6" (14.63 × 2.591 × 2.896 m)
Internal: 47' 5" × 8' 2" × 8' 10"
Door: 8' 2" × 8' 6"
Tare 9500 lb (4310 kg) · Max payload 57700 lb (26170 kg) · Max gross 67200 lb (30480 kg)
Capacity 3454 cu ft (97.8 cbm) · Floor 387 sq ft · Pallets 26 GMA / 30 Euro
US price 2026: used $3000–5500, new (one-trip) $5500–8500
Best for: US domestic rail/truck box — 6 inches wider inside than ISO boxes, which two pallet rows appreciate.
Note: 48s and 53s are 8'6" wide — they never sail. They live on US rails and highways, which is why they're cheap inland.

### 53ft Domestic (ISO domestic (AAR))
External: 53' 0" × 8' 6" × 9' 6" (16.154 × 2.591 × 2.896 m)
Internal: 52' 5" × 8' 2" × 8' 10"
Door: 8' 2" × 8' 6"
Tare 11110 lb (5040 kg) · Max payload 56090 lb (25440 kg) · Max gross 67200 lb (30480 kg)
Capacity 3830 cu ft (108.4 cbm) · Floor 428 sq ft · Pallets 30 GMA / 34 Euro
US price 2026: used $3500–6000, new (one-trip) $6000–9500
Best for: The biggest single box you can buy: 428 sq ft — a genuine studio apartment in one piece of steel.
Note: One 53ft domestic container holds the cargo of roughly 3.3 TEU — the most space per crane lift in North America.

### 20ft Refrigerated (ISO 22R1)
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: 17' 10" × 7' 6" × 7' 5"
Door: 7' 6" × 7' 3"
Tare 6610 lb (3000 kg) · Max payload 60590 lb (27480 kg) · Max gross 67200 lb (30480 kg)
Capacity 1000 cu ft (28.3 cbm) · Floor 134 sq ft · Pallets 9 GMA / 10 Euro
US price 2026: used $4500–9000, new (one-trip) $10000–18500
Best for: Plug-in cold room: −20°F to +70°F on 3-phase power. Working units carry meat, produce, vaccines — and restaurant overflow.
Note: A reefer's machinery eats two feet of length: you pay 20ft outside, you get 17'10" inside.

### 40ft Refrigerated High Cube (ISO 45R1)
External: 40' 0" × 8' 0" × 9' 6" (12.192 × 2.438 × 2.896 m)
Internal: 38' 0" × 7' 6" × 8' 4"
Door: 7' 6" × 8' 0"
Tare 9900 lb (4480 kg) · Max payload 65060 lb (29520 kg) · Max gross 74960 lb (34000 kg)
Capacity 2380 cu ft (67.3 cbm) · Floor 285 sq ft · Pallets 20 GMA / 23 Euro
US price 2026: used $8000–12600, new (one-trip) $16000–29000
Best for: Industrial cold storage by the box: 285 sq ft of walk-in freezer that arrives on a truck.
Note: Nearly all 40ft reefers are high cubes — the insulation would steal too much headroom from a standard-height box.

### 20ft Open Top (ISO 22U1)
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: 19' 4" × 7' 7" × 7' 8"
Door: 7' 6" × 7' 2"
Tare 5290 lb (2400 kg) · Max payload 61910 lb (28080 kg) · Max gross 67200 lb (30480 kg)
Capacity 1136 cu ft (32.2 cbm) · Floor 147 sq ft · Pallets 10 GMA / 11 Euro
US price 2026: used $3000–5500, new (one-trip) $5000–8000
Best for: Crane-loaded cargo: machinery, glass, timber. The roof is a removable tarpaulin on steel bows.
Note: Open tops carry 'in-gauge' cargo under tarp — if the load pokes above the roofline, it books as out-of-gauge and the price jumps.

### 40ft Open Top (ISO 42U1)
External: 40' 0" × 8' 0" × 8' 6" (12.192 × 2.438 × 2.591 m)
Internal: 39' 5" × 7' 7" × 7' 8"
Door: 7' 6" × 7' 2"
Tare 8490 lb (3850 kg) · Max payload 58710 lb (26630 kg) · Max gross 67200 lb (30480 kg)
Capacity 2350 cu ft (66.5 cbm) · Floor 299 sq ft · Pallets 21 GMA / 25 Euro
US price 2026: used $4000–7000, new (one-trip) $6500–10000
Best for: Long machinery and structural steel that only a crane can load.
Note: The removable roof bows are numbered — lose one and the tarp won't tension, and surveyors will fail the box for sea duty.

### 20ft Flat Rack (ISO 22P1)
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: 18' 5" × 7' 3" × 7' 3"
Door: — × —
Tare 6060 lb (2750 kg) · Max payload 68900 lb (31250 kg) · Max gross 74960 lb (34000 kg)
Specialist format (no closed cargo volume)
US price 2026: used $3500–6000, new (one-trip) $6000–9500
Best for: A steel deck with fold-down ends: boats, transformers, vehicles, anything too wide or too heavy for a closed box.
Note: Flat racks routinely out-lift closed boxes: a 20ft rack is rated to carry more payload than a 40ft dry container.

### 40ft Flat Rack (ISO 42P3)
External: 40' 0" × 8' 0" × 8' 6" (12.192 × 2.438 × 2.591 m)
Internal: 39' 7" × 6' 10" × 6' 5"
Door: — × —
Tare 12570 lb (5700 kg) · Max payload 86640 lb (39300 kg) · Max gross 99210 lb (45000 kg)
Specialist format (no closed cargo volume)
US price 2026: used $5000–9000, new (one-trip) $8000–14000
Best for: The heavy-haul workhorse: up to 86,000 lb of machinery on a 40ft steel spine.
Note: A 40ft flat rack's frame rails are the heaviest steel in the container world — the tare alone outweighs an empty 40ft HC by half.

### 20ft Tank (ISO Tank) (ISO 22K2 (T11))
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: — × — × —
Door: — × —
Tare 8380 lb (3800 kg) · Max payload 70990 lb (32200 kg) · Max gross 79370 lb (36000 kg)
Capacity 918 cu ft (26 cbm) · Floor 0 sq ft · Pallets 0 GMA / 0 Euro
US price 2026: used $8000–15000, new (one-trip) $18000–35000
Best for: A stainless pressure vessel in an ISO frame: food liquids, chemicals, fuel — 26,000 liters per lift.
Note: An ISO tank must ship at least 80% full (to stop deadly liquid surge) and at most 95% full (for thermal expansion).

### 20ft Double Door (Tunnel) (ISO 22G1 (tunnel))
External: 20' 0" × 8' 0" × 8' 6" (6.058 × 2.438 × 2.591 m)
Internal: 19' 2" × 7' 8" × 7' 10"
Door: 7' 8" × 7' 6"
Tare 5290 lb (2400 kg) · Max payload 61910 lb (28080 kg) · Max gross 67200 lb (30480 kg)
Capacity 1160 cu ft (32.9 cbm) · Floor 149 sq ft · Pallets 10 GMA / 11 Euro
US price 2026: used $2800–4500, new (one-trip) $4500–7000
Best for: Doors at both ends: drive-through vehicle storage, divided rentals, and workshops with a real flow path.
Note: Tunnel boxes solve the container's oldest annoyance — the thing you need is always at the far end.

### 40ft Open Side (ISO 45G1 (side))
External: 40' 0" × 8' 0" × 9' 6" (12.192 × 2.438 × 2.896 m)
Internal: 39' 6" × 7' 8" × 8' 10"
Door: full side × 8' 5"
Tare 10360 lb (4700 kg) · Max payload 56840 lb (25780 kg) · Max gross 67200 lb (30480 kg)
Capacity 2694 cu ft (76.3 cbm) · Floor 300 sq ft · Pallets 21 GMA / 25 Euro
US price 2026: used $5500–9000, new (one-trip) $8000–12500
Best for: The whole 40ft wall opens as bi-fold doors — forklift every pallet straight in, or build a pop-up bar that opens wide.
Note: Open-side boxes are the darling of container bars and shops: the wall becomes the storefront.

## Frequently asked questions

## Sizes & dimensions

Q: What are the standard shipping container sizes?
A: The two worldwide standards are 20ft (20' × 8' × 8'6") and 40ft (40' × 8' × 8'6"), plus the 40ft high cube at 9'6" tall. Around them sit 10ft, 20ft HC, 45ft HC and — in North America only — 48ft and 53ft domestic boxes. All ISO boxes are exactly 8 feet wide.

Q: What are the actual dimensions of a 20-foot shipping container?
A: Externally 20' × 8' × 8'6" (6.06 × 2.44 × 2.59 m). Inside you get 19'4" × 7'8" × 7'10" — 1,172 cubic feet, about 150 sq ft of floor. The door opening is 7'8" wide × 7'6" tall.

Q: Are all shipping containers 8 feet wide?
A: All ISO ocean containers are exactly 8'0" (2.438 m) wide — it's the one dimension that never varies. The exceptions never sail: US domestic 48ft and 53ft boxes are 8'6" wide, and European pallet-wide containers are about 2.5 m.

Q: How tall is a shipping container?
A: Standard boxes are 8'6" (2.59 m) tall; high cubes are 9'6" (2.90 m). Inside that means roughly 7'10" and 8'10" of clear height respectively — the extra foot matters most in conversions, where insulation eats 3–6 inches.

Q: How much floor space is in a 40ft container?
A: About 300 sq ft (27.8 m²) — internally 39'6" × 7'8". Two 40-footers side by side give you a genuine one-bedroom footprint of 600 sq ft.

Q: What does 'high cube' mean?
A: A high cube (HC) container is one foot taller than standard: 9'6" external instead of 8'6". Same length, same width, same max gross weight — just 12–14% more volume. Nearly all new 40ft production is high cube.

Q: How many CBM is a 20ft and a 40ft container?
A: A 20ft holds 33.2 cbm (1,172 cuft); a 40ft standard holds 67.7 cbm (2,390 cuft); a 40ft high cube holds 76.3 cbm (2,694 cuft). Real-world loading typically achieves 85–90% of these figures.

Q: How many pallets fit in a shipping container?
A: A 20ft fits 10 standard US (GMA 48"×40") pallets or 11 Euro pallets in one layer. A 40ft fits 21 GMA or 25 Euro pallets. A 53ft domestic box takes about 30 GMA pallets thanks to its extra 6 inches of width.

Q: What is the door opening size of a container?
A: Standard boxes: 7'8" wide × 7'6" tall (2.34 × 2.28 m); high cubes give 8'6" of door height. If your cargo is taller than 7'6", you need a high cube or an open top.

## Weight & capacity

Q: How much does a shipping container weigh?
A: Empty (tare): a 20ft weighs about 4,850 lb (2,200 kg); a 40ft standard about 8,000 lb (3,630 kg); a 40ft high cube about 8,750 lb (3,970 kg). Both 20ft and 40ft are rated to the same 67,200 lb (30,480 kg) max gross.

Q: How much weight can a shipping container hold?
A: A 20ft can legally carry about 62,350 lb (28,280 kg) of cargo; a 40ft about 59,200 lb — the 20ft actually wins on payload because its own steel weighs less. On US highways, road limits (~44,000 lb of cargo) bind before the box does.

Q: What is tare weight, payload and max gross?
A: Tare is the empty box; payload is the cargo it may carry; max gross = tare + payload, the total rated weight stamped on the CSC plate on the door. For most modern boxes max gross is 30,480 kg (67,200 lb).

Q: Can you stack shipping containers?
A: Yes — that's the whole point of the corner castings. At sea they stack 9–11 high; on land a static, well-founded stack of 2–3 is routine. Weight passes through the four corner posts, so stacks must align casting-to-casting, never mid-span.

Q: How strong is a container roof?
A: The roof sheet itself is only rated for about 660 lb (300 kg) over a small area — it's the corner posts that are strong, each taking over 210,000 lb. Walk gently on a roof; build roof decks on frames that land the load on the castings.

## Prices & buying

Q: How much does a shipping container cost?
A: In the US in 2026: used 20ft $1,500–3,000; used 40ft $2,000–4,500; new (one-trip) 20ft $2,500–5,500; new 40ft HC $4,000–7,000. Delivery adds 15–40%. Working 40ft reefers run $8,000–12,600 used.

Q: How much should I pay for a 20ft shipping container?
A: $1,500–2,500 for a used cargo-worthy unit, $2,500–3,500 for premium used, $3,000–5,500 for a one-trip. Below $1,500 expect significant rust or a scam — pay by card, never wire transfer to an unknown seller.

Q: What do the container grades mean (one-trip, CW, WWT, as-is)?
A: One-trip: made one loaded voyage, near-new. Cargo-worthy (CW): certified structurally fit for shipping. Wind & watertight (WWT): sealed but not certified — fine for storage. As-is: expect holes, rot or door problems. For conversions, buy one-trip or high-grade CW.

Q: Where can I buy a shipping container?
A: Four channels: national online retailers (Container One, Boxhub, Western Container Sales), regional depots (cheapest delivery), leasing-company sell-offs, and marketplaces like eBay or Facebook (highest scam risk). Always confirm the exact unit number and inspect or get dated photos before paying.

Q: Is it cheaper to rent or buy a container?
A: Rental runs $75–250/month for storage boxes. If you need it longer than 18–24 months, buying usually wins — a used 20ft at $2,000 pays for itself vs $100/month rent in under two years, and you keep resale value of roughly 50–70%.

Q: Do shipping containers hold their value?
A: Yes, unusually well: a well-kept used box typically resells for 50–80% of its purchase price years later. Container prices track steel and freight cycles, so buying in a freight slump (like 2023–24) beats buying in a boom (2021).

Q: What is the average lifespan of a shipping container?
A: 10–12 years in ocean service, then another 15–25+ years on land. A one-trip box that's kept painted and dry can pass 30 years as a building or store. The killers are standing water on the roof and untreated scratches down to bare steel.

## Delivery & installation

Q: How are shipping containers delivered?
A: Usually on a tilt-bed (roll-off) truck that slides the box onto the ground — you need about 100 ft of straight clearance for a 40ft delivery and 60 ft for a 20ft. No crane needed on accessible sites; a crane day adds $800–2,500.

Q: Do you need a concrete slab for a shipping container?
A: No. A container needs support only at its four corner castings: concrete blocks, poured piers or railroad ties work for storage. A full slab is only worth it for permitted buildings or point-loaded multi-box stacks. What matters is level — more than 1–2 inches of twist and the doors stop closing.

Q: Do I need a permit to put a container on my property?
A: For temporary storage, often no — many counties allow 30–180 days unpermitted. As a permanent structure or dwelling, almost always yes: zoning approval plus building permit. Rules are county-by-county; HOAs are frequently stricter than the county.

Q: Can a tornado pick up a shipping container?
A: An empty 20ft (≈4,850 lb) can be moved or rolled by EF2+ winds; loaded or anchored boxes are dramatically more stable. For wind-zone installs, anchor the corner castings to piers or ground anchors — an anchored container is among the most wind-resistant small structures you can put on a site.

Q: How do you keep a container from sweating inside?
A: "Container rain" is condensation on cold steel. Fixes, in escalating order: vents at both ends for airflow, desiccants for stored goods, insulation (closed-cell spray foam is the standard) for occupied boxes. Skip insulation in a lived-in box and the walls will literally drip.

## Container homes & conversions

Q: How much does a container home really cost?
A: All-in US figures: a DIY-heavy 20ft cabin $15,000–48,000; a turnkey 40ft one-bedroom $70,000–110,000; multi-container customs $150,000–300,000+. The four lines the '$30k home!' ads skip: foundation, delivery, utility hookups, and permits.

Q: Are container homes worth it?
A: They win on speed (weeks, not months), price certainty from prefab builders, and durability. They don't win on cost per square foot vs stick framing once you pass ~2 containers — buy them for the speed, strength and look, not as a guaranteed discount.

Q: Which container is best for a home?
A: The 40ft high cube is the standard answer: 300 sq ft, 8'10" internal height (so you keep 8ft ceilings after insulation), and the best price per square foot. One-trip condition is worth the premium — you're building a house on that steel.

Q: How long does a container home last?
A: 50+ years is realistic for a one-trip box that's properly painted, sealed and kept dry — the same corten-family steel bridges are made of. The practical lifespan is set by maintenance: repaint scratches, keep the roof draining, control interior humidity.

Q: Can you finance a container home?
A: Yes, but not usually with a standard mortgage. Routes: personal/RV-style loans for small builds, construction-to-perm loans where the home sits on a permanent foundation and meets code, and builder financing from larger prefab companies. Insurance follows the same logic — permanent foundation and code compliance unlock normal products.

Q: Are container homes legal everywhere?
A: No. They're broadly legal in rural and many suburban US zones, restricted in some cities and most HOAs. The gating factors: local zoning, state building codes (Texas, California and Florida are the most container-experienced), and whether your design gets an engineer's stamp.

## Reefers & specialty boxes

Q: What is a reefer container?
A: A refrigerated container with a built-in cooling unit holding −20°F to +70°F, powered by 3-phase 440–460V. A working 20ft reefer costs $4,500–9,000 used; non-working 'insulated' units sell cheaper and make excellent cold-room shells.

Q: How much power does a reefer use?
A: Typically 5–10 kWh per hour of active cooling depending on setpoint and ambient — figure $15–35/day at US commercial rates. For static cold storage, a soft-start single-to-3-phase converter is a common site fix.

Q: What is an open-top container for?
A: Cargo that loads by crane: machinery, glass, structural steel, logs. The roof is a removable tarpaulin over steel bows; dimensions otherwise match a standard box within an inch or two.

Q: What is a flat rack used for?
A: Oversized and overweight loads: vehicles, boats, transformers, industrial machines. It's a heavy steel deck with fixed or collapsible end walls — a 40ft flat rack carries up to 86,000 lb, more than any closed box.

Q: What do the letters and numbers on a container mean?
A: The 11-character unit number (like MSCU 123456 7) is the BIC code: 4 letters (owner + 'U'), 6 digits, and a check digit computed from the rest. The separate 4-character code like 45G1 is the ISO size-type: first digit length, second height, letters for the type.