24 × 18 × 18 in box: dimensions, dim weight and strength
A 24 × 18 × 18 in box holds 7,776 in³ (4.5 ft³) inside. Made in C flute its outside is about 24.31 × 18.31 × 18.47 in, which dimensional weight bills USPS at 65 lb and FedEx at 56 lb.
Key numbers
| Inside (L × W × H) | 24 × 18 × 18 in |
|---|---|
| Inside volume | 7,776 in³ · 4.5 ft³ · 127.4 L |
| Inside, metric | 610 × 457 × 457 mm |
| Perimeter 2(L + W) | 84 in |
| Length + girth, C flute OD | 97.9 in |
Outside dimensions by flute
| Board | Caliper, in | Outside, in | Outside volume, ft³ |
|---|---|---|---|
| E flute | 0.063 | 24.13 × 18.13 × 18.19 | 4.602 |
| B flute | 0.125 | 24.25 × 18.25 × 18.38 | 4.706 |
| C flute | 0.156 | 24.31 × 18.31 × 18.47 | 4.759 |
| EB double wall | 0.188 | 24.38 × 18.38 × 18.56 | 4.811 |
| BC double wall | 0.281 | 24.56 × 18.56 × 18.84 | 4.972 |
OD ≈ ID + 2 calipers on length and width, + 3 on depth. An estimate: your box maker sets the scores. Convert other sizes.
Dimensional weight
| Carrier | Divisor | Measured, in (C) | DW, C flute | DW, BC double wall |
|---|---|---|---|---|
| USPS | 139 | 25 × 19 × 19 | 65 lb | 65 lb |
| FedEx | 139 | 24 × 18 × 18 | 56 lb | 65 lb |
DW = ⌈L × W × H ÷ divisor⌉ on outside dimensions, after each carrier's own rounding. USPS applies it only above 1,728 in³ (n/a means it bills actual weight). The carrier bills the greater of actual and dimensional weight. Divisors checked on carrier pages 2026-10-27; try your own weight.
Estimated compression strength
| Board | BCT, lbf | After 30 days storage |
|---|---|---|
| 32 ECT B flute | 609 | 365 |
| 32 ECT C flute | 681 | 408 |
| 44 ECT C flute | 936 | 561 |
| 48 ECT C flute | 1,021 | 612 |
| 48 ECT BC double wall | 1,370 | 822 |
| 61 ECT BC double wall | 1,741 | 1,044 |
| 71 ECT BC double wall | 2,026 | 1,216 |
Simplified McKee: BCT ≈ 5.87 × ECT × √(caliper × 84). The 30-day column applies Packgent's default 40% storage loss, an assumption. Estimates only; test with ASTM D642.
Pallet pattern on 48 × 40
| Board | Per layer | Layers | Boxes per pallet | Load height, in | Cube used |
|---|---|---|---|---|---|
| C flute | 3 | 2 | 6 | 42.4 | 47% |
| BC double wall | 3 | 2 | 6 | 43.2 | 49% |
Column stacked, no overhang, on a 48 × 40 in deck 5.5 in tall, loaded to 60 in overall. Those three are assumptions you can change in the pallet calculator. Pattern: two-zone (1 rows turned).
Blank size in C flute
| Style | Blank, in | Board, ft² |
|---|---|---|
| 0201 RSC | 85.88 × 36.31 | 21.66 |
| 0200 HSC | 85.88 × 27.16 | 16.19 |
| 0203 FOL | 85.88 × 54.31 | 32.39 |
With one caliper allowance per score. Multiply board area by your board's combined weight (lb/MSF ÷ 1,000) for box weight, or use the box weight calculator.
Sources
- USPS Domestic Mail Manual 223 (Priority Mail prices and eligibility), section 1.4
- FedEx: What is dimensional weight?
- Flute calipers: Foster (1997), Wiley Encyclopedia of Packaging Technology
- McKee, Gander & Wachuta (1963), Paperboard Packaging 48(8)
Last reviewed . See all sources and how Packgent computes.
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