Container Dimensions and Specifications:

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Data source: ISO 668:2020 standard, official container type parameter tables of various shipping lines

I. Standard Dry Container Internal and External Dimensions Table

The following data adopts the ISO 668:2020 standard and are common parameters for international ocean shipping.

Parameter	20GP	40GP	40HQ	45HQ
External length (mm)	6,058	12,192	12,192	13,716
External width (mm)	2,438	2,438	2,438	2,438
External height (mm)	2,591	2,591	2,896	2,896
Internal length (mm)	5,898	12,032	12,032	13,556
Internal width (mm)	2,352	2,352	2,352	2,352
Internal height (mm)	2,393	2,393	2,698	2,698
Door width (mm)	2,340	2,340	2,340	2,340
Door height (mm)	2,280	2,280	2,585	2,585
Volume (CBM)	33.1	67.5	76.0	86.0
Max payload (kg)	28,200	28,800	28,620	27,800
Tare weight (kg)	2,200	3,700	3,900	4,200
Max gross weight (kg)	30,480	32,500	32,500	32,000

Data source: ISO 668:2020 standard + official container type parameter tables from Maersk/MSC/COSCO shipping lines. For detailed parameter comparisons and selection recommendations for each container type, see the Container Type Encyclopedia.

II. Key Points of Dimension Comparison

2.1 20GP vs 40GP

Comparison	20GP	40GP	Difference
Length	Approx. 6 m	Approx. 12 m	40GP is exactly twice 20GP
Volume	33.1 CBM	67.5 CBM	40GP is not twice 20GP (+104%)
Payload	28,200 kg	28,800 kg	Payload is almost the same; 40GP has low payload utilization

Key information: The volume of 40GP is about twice that of 20GP, but the payload is almost the same. Therefore, heavy cargo is suitable for 20GP, and light bulky cargo is suitable for 40GP.

2.2 40GP vs 40HQ

Comparison	40GP	40HQ	Difference
Internal height	2,393 mm	2,698 mm	305 mm higher
Door height	2,280 mm	2,585 mm	305 mm higher
Volume	67.5 CBM	76.0 CBM	8.5 CBM more (+13%)

Key point: The external length, width, and footprint of the two container types are exactly the same; the only difference is the internal height. When loading light bulky cargo and the stacking height of a single piece is within 2.4 m, 40HQ has more usable volume; if the cargo height does not exceed 2.3 m and the weight is already close to the limit, 40GP is more suitable.

2.3 40HQ vs 45HQ

Comparison	40HQ	45HQ	Difference
Internal length	12,032 mm	13,556 mm	1.5 m longer
Volume	76.0 CBM	86.0 CBM	10 CBM (+13%) more
Application scenarios	International standard routes	North America inland dedicated routes	45HQ is mainly used on North American routes

Key information: 45HQ is not available on all routes and is mainly used on routes such as North America and Northern Europe. Before booking, confirm whether the shipping line provides this container type.

III. Differences in Road Weight Limits by Country

The maximum payload of a container is not only limited by the container itself but also constrained by the road weight limit of the destination country. This is the aspect most easily overlooked by foreign trade companies.

Country/Region	Road weight limit (including container weight)	Recommended maximum cargo load for 20GP	Recommended maximum cargo load for 40GP	Notes
China	30,480kg (20GP) / 32,500kg (40GP)	≤28,000kg	≤28,500kg	Subject to the container nameplate
United States	Approx. 23,000-24,000kg (federal highway weight limit)	≤20,000kg	≤20,000kg	🔴 Most stringent weight limit
European Union	Approx. 26,000-28,000kg (varies slightly by country)	≤23,000kg	≤23,000kg	Germany/France/Netherlands are stricter
United Kingdom	Approx. 26,000kg	≤23,000kg	≤23,000kg	—
Australia	Approx. 24,000-26,000kg	≤21,000kg	≤21,000kg	Weight limits vary by state
Southeast Asia	Approx. 26,000-30,000kg	≤24,000kg	≤24,000kg	Relatively lenient

Actual Loading Capacity Due to Weight Limits

Take 20GP as an example:
Container maximum payload: 28,200kg
US road weight limit: ~23,000kg (including container weight)
Actual usable payload: 23,000 - 2,200 (container tare weight) = 20,800kg
Lost payload: 28,200 - 20,800 = 7,400kg (26%)

Practical recommendations:

EU route: Road weight limits in Germany/France/Netherlands and other countries are about 26,000-28,000kg (including container weight), and it is recommended that 20GP loading not exceed 23,000kg. Overweight fines in the EU vary by member state; it is recommended to confirm the specific weight limit of the destination country before loading.
US route: The federal highway weight limit is about 23,000kg (including container weight), and it is recommended that 20GP loading not exceed 20,000kg. Overweight fines in the United States are stricter than in the EU.

IV. Quick Reference for Volume Calculation

4.1 Standard Pallet Loading Capacity

Container type	Number of standard pallets	Pallet specification (1200×1000mm) arrangement
20GP	10	5 rows × 2 columns
40GP	21-22	10 rows × 2 columns + 1-2 in the rear row
40HQ	24-26	11-12 rows × 2 columns (double stacking possible due to height advantage)
45HQ	26-28	12-13 rows × 2 columns

4.2 Quick Volume Estimation

Container type	Theoretical volume	Actual usable volume (including gaps)	Utilization rate
20GP	33.1CBM	25-28CBM	75%-85%
40GP	67.5CBM	55-60CBM	80%-88%
40HQ	76.0CBM	63-68CBM	83%-90%
45HQ	86.0CBM	70-76CBM	82%-88%

Why is the actual usable volume smaller than the theoretical volume? Because protruding corner castings inside the container, corrugated side walls, and securing gaps between cargo occupy some space. When actually loading, it is recommended to budget based on 80%-85% of the theoretical volume. For container type selection decisions, refer to the selection process in the Container Types Encyclopedia.

V. Pre-Loading Weight Limit Checklist

□ Confirm the maximum payload on the container CSC nameplate
□ Confirm the destination country's road weight limit (especially the US and EU)
□ Calculate the total weight of all cargo (including pallets and packaging materials)
□ Confirm whether cargo weight + container weight exceeds the road weight limit
□ Confirm that the weight of a single pallet does not exceed the container floor rated load (3-4 tons/axle)
□ If overweight: adjust the stowage plan or ship in batches

Data note: The weight limit data above are common industry reference values, and policies in each country/shipping company may be adjusted at any time. Before loading, it is recommended to confirm the latest weight limit policy with the freight forwarder.

Frequently Asked Questions

How do I choose between 20GP and 40GP?

Look at density. If the same shipment is already close to the weight limit when loaded into a 20GP, it is heavy cargo. Switching to a 40GP will not increase the weight capacity and the volume will not be fully used; it simply takes up a larger container slot. For cargo that is bulky and light, the 40GP offers higher transport efficiency per unit of volume.

How much more can a 40HQ hold than a 40GP?

The internal height is 305 mm greater, and the theoretical capacity increases from 67.5CBM to 76.0CBM, an increase of 8.5CBM (about 13%). The two container types have the same external length and width and occupy the same yard space and vessel slot. Actual loading capacity also depends on whether the packaging can be stacked within a height of 2.4 m and whether the total weight has reached the weight limit.

Container Dimensions and Specifications: Internal/External Dimensions and Weight Limits for 20GP/40GP/40HQ/45HQ