How many 18 × 18 × 16 in boxes fit in a 20ft reefer?
18 × 18 × 16 in boxes of 457 × 457 × 406 mm (also called 3 cubic foot boxes, medium moving boxes) in a 20-foot refrigerated container (20RF) — inner dimensions 5,444 × 2,294 × 2,276 mm. Calculated by the Cubestow engine on 2026-09-08.
Boxes may be laid on any side. 94% of the space used, 5 layers high, about 4,410 kg (16% of payload). Open this load in the 3D planner →
Top view — floor layer (65 on the floor)
Side view — first row along the wall (5 layers)
The answer in detail
The "3.0 cubic foot" medium moving box (18 × 18 × 16 in) is the box most US movers use for the bulk of a household. Lying it on its side gains height in some containers, which is why the any-orientation count is higher.
The refrigeration unit and insulated walls take space, so a reefer is shorter, narrower and lower inside than a dry 20ft. Leave the T-floor and the air return clear.
The simple grid estimate is 11 along the length × 5 across × 5 high = 275. The engine found 315 — 40 more than either uniform grid — by mixing orientations so that the leftover strip along the wall is used and by choosing the orientation that gives the most layers. The top view above shows the pattern.
Variants
| Loading rule | Fits | Layers | Volume used | Total weight |
|---|---|---|---|---|
| Boxes may be laid on any side (headline figure) | 315 | 5 | 94% | 4,410 kg (16% of payload) |
| Boxes kept this-side-up (turned on the floor plane only) | 275 | 5 | 82% | 3,850 kg (14% of payload) |
How many 20ft reefers for a given order?
| 18 × 18 × 16 in boxes | 100 | 250 | 500 | 1,000 | 2,500 | 5,000 |
|---|---|---|---|---|---|---|
| 20ft reefers needed | 1 | 1 | 2 | 4 | 8 | 16 |
| Last one filled to | 32% | 79% | 59% | 17% | 94% | 87% |
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Frequently asked
How many 18 × 18 × 16 in boxes fit in a 20ft reefer?
315 18 × 18 × 16 in boxes of 457 × 457 × 406 mm fit in a 20ft reefer (inner dimensions 5,444 × 2,294 × 2,276 mm), boxes may be laid on any side. That uses 94% of the 28.4 m³ available and weighs about 4,410 kg.
What are the inner dimensions of a 20ft reefer?
Typical inner dimensions are 5,444 mm long, 2,294 mm wide and 2,276 mm high (214.3 × 90.3 × 89.6 in), giving 28.4 m³ of space and a rated payload of about 27,400 kg. Individual units vary by a few centimetres, so check the actual box for tight loads.
How much does a full load of 18 × 18 × 16 in boxes weigh?
315 × 14 kg ≈ 4,410 kg, which is 16% of the 27,400 kg payload — so this load is limited by space, not weight.
How was this number calculated?
By running the Cubestow 3D load-planning engine on the exact dimensions above, allowing all six orientations, stacking with at least 80% base support and the container's payload limit, then re-validating the plan for overlaps, support and weight. Real loads leave room for dunnage, door clearance and uneven cartons, so treat the figure as the practical maximum.