Where 48 and 40 come from
The footprint is trailer arithmetic, not tradition. Forty-eight by forty inches is 1,920 square inches, or 13.3 square feet of deck. Two pallets side by side take 96 inches of floor, and a dry van measures 98 to 100 inches between the walls, so a 53-foot trailer carries 26 to 30 of them with a two-to-four-inch strip left over. Nothing else in the standard range fills that floor as tightly.
The 40-inch side is the one people ignore, and it is the one that decides whether a load goes two abreast. Add an inch of overhang on each side and the pair needs 100 inches. On a 98-inch floor that shipment goes single file, which is the same freight moving in roughly twice the trailer.
Every conveyor, rack bay, pallet jack and case dimension in the grocery chain was built around those two numbers, which is why the format outlived the association that wrote it.
Who owns the specification
The Grocery Manufacturers Association set the guidelines while it represented the large food and beverage manufacturers whose products filled the pallets. In 2020 the association renamed itself the Consumer Brands Association. The pallet kept the old initials, and suppliers still sell "GMA pallets" rather than "CBA pallets".
It is a trade guideline, not a regulation. Nobody inspects a pallet at the dock gate for compliance, which is exactly why the numbers on the drawing and the numbers on the pallet drift apart.
The tolerances that are actually written down
| Specification | What the written standard allows |
|---|---|
| Footprint | 48 × 40 in (1,219 × 1,016 mm), 13.3 ft² of deck |
| Overall height | 5 to 6.5 in, set by deck board thickness of 3/8 to 5/8 in |
| Deck boards | 7 on top, 5 on the bottom, 40 in wide, gaps up to 3.5 in |
| Stringers | Three, 48 in long, 3.5 in tall, 1 3/8 in thick |
| Squareness | Up to 1 in out of square is accepted in graded recycled stock |
| Entry and rating | Four-way entry with notches on the width side; 2,500 lb minimum, 2,500 to 4,600 lb by grade |
A pallet that is an inch out of square no longer measures 48 by 40 at its widest point, and a load built square to the deck inherits that error all the way up the stack.
Load rating and what the wood weighs
The floor of the rating is 2,500 pounds. Graded stock is commonly sold between 2,500 and 4,600 pounds, depending on grade and on whether the load is static, dynamic or racked. Empty weight runs 33 to 49 pounds for a standard wood pallet and 55 to 66 pounds for reinforced or premium stock. A heat-treated 48 × 40 export pallet rated at 2,500 pounds ships at 40 pounds.
Both numbers matter to a freight bill, and neither one is printed on the pallet.
What the pallet adds to the cube
48 × 40 × 6.5 inches is 12,480 cubic inches, or 7.22 cubic feet of pallet. That cube is real, because a carrier measuring your shipment measures from the floor to the top of the highest carton. The deck height sits inside the number whether you counted it or not.
Take cartons stacked 54 inches tall on a 48 × 40 pallet. The cartons alone are 48 × 40 × 54 = 103,680 cubic inches, which is 60.00 cubic feet. With the pallet, the same load is 48 × 40 × 60.5 = 116,160 cubic inches, which is 67.22 cubic feet. The pallet adds 12 percent to the cube of a 54-inch load, and the percentage climbs as the load gets shorter: on a 30-inch stack the pallet is 22 percent of the cube.
The weight helps, the height hurts more
A 700-pound load of cartons on a 40-pound pallet, measured the way the carrier measures it, is 740 pounds over 67.22 cubic feet, which is 11.01 pcf and class 92.5. Measure the cartons only, 740 pounds over 60.00 cubic feet, and you get 12.33 pcf and class 85.
The pallet's own 40 pounds push density up, which is the direction you want. Its 6.5 inches of height push density down by more than the weight lifts it, which is the direction you do not. Quote from the carton measurement and you will say 85; the carrier measures the pallet and bills 92.5. The bands, 400 down to 50, are on the freight class chart page.
Overhang costs a class before it costs a claim
A load that overhangs one inch on each side measures 50 × 42 instead of 48 × 40. On the same 60.5-inch stack that is 73.52 cubic feet rather than 67.22, which is 9.4 percent more cube for cargo that did not grow. An 820-pound shipment reads 12.20 pcf at 48 × 40 and 11.15 pcf at 50 × 42, so class 85 turns into class 92.5 without a single carton being added. Then it reaches the trailer and hits the width problem above.
What to put on the paperwork
Measure to the top of the highest carton, including the deck. Write the pallet type and its empty weight on the bill of lading next to the piece count, and write the footprint you actually measured rather than the one the pallet was sold as. When a reweigh or a reclass lands three weeks later, those three lines are the difference between an argument you settle with numbers and one you settle by paying.