Opening (pallet fork opening)
Also called: fork opening, entry opening, fork pocket
An opening is the clear space between the decks and between stringers or blocks that fork tines or pallet-jack forks enter. It is described by its width and its height.
In depth: Pallets for automation: conveyors, AS/RS and robotic palletizers
Every pallet has openings on the sides where forks can enter. Their size decides which trucks, pallet jacks and automated handlers can use the pallet.
How it is measured
- Width: the clear distance between two stringers or two blocks.
- Height: the clear distance from the underside of the top deck to the top of the bottom deck, or to the floor where there is no bottom board. See entry height.
Typical values
| Pallet | Opening width | Opening height |
|---|---|---|
| GMA-style 48 × 40, end entry | 17.94 in (456 mm) between 1-3/8 in stringers | 3.5 in (89 mm) |
| GMA-style 48 × 40, side entry through notches | 9 in (229 mm) notch length | About 1-7/8 in (48 mm) |
| Plastic rackable 48 × 40 (one published model) | 13.1 in long side, 12.0 in short side | 3.5 in |
The GMA widths are calculated from a common design. Plastic values are one manufacturer's published figures and differ by model.
Why it matters
Fork tines are commonly about 4 in (100 mm) wide, so openings must be wide enough for both tines at the truck's spacing. Pallet jacks need openings that reach the floor so their wheels can drop. Automated systems (AS/RS, shuttles, robotic trucks) often specify minimum opening sizes. See pallets for automation.
On a spec sheet
Openings show on the end and side views as the bay widths between stringers or blocks and the stringer or block height. Plastic pallet data sheets often publish "fork tunnel" width × height per side.
Related
- GlossaryEntry height (pallet)Entry height is the clear vertical height of a pallet's fork opening, from the floor or bottom deck to the underside of the top deck. On a 2-way stringer pallet it equals the stringer height, typically 3-1/2 in (89 mm).
- GlossaryFork entry (pallet)Fork entry is the set of sides from which forklift tines or pallet-jack forks can enter a pallet. Pallets are classed as 2-way, partial 4-way or full 4-way entry.
- GlossaryWhat is a pallet notch?A notch is a cutout in the lower edge of a pallet stringer that lets forklift tines enter from the sides, making the pallet partial four-way. A typical 48 × 40 notch is 9 in long and 1-1/4 in deep, starting 6 in from each end.
- GlossaryFork tinesFork tines are the two steel arms on a forklift or pallet jack that slide into a pallet's openings to lift it. Their width, thickness, length and spacing set the minimum size of the pallet's openings and affect its dynamic load rating.
- GuidesPallets for automation: conveyors, AS/RS and robotic palletizersAutomated systems need consistent, flat, stiff pallets. Bottom boards must cross the conveyor supports (perpendicular to rollers, across chain strands), gaps must not snag, flatness is often held to 1/4 in or better, and AS/RS racks commonly limit sag to 0.5 in. Perimeter-base block and plastic pallets run either way.
- ComparisonsTwo-way vs four-way pallets: entry types explainedA two-way pallet takes forks from two opposite ends only. A four-way pallet takes forks from all four sides; partial four-way (notched stringers) admits forklifts but not pallet jacks from the sides. Choose two-way for low cost and fixed flows, four-way for flexible handling and trailer loading.
More in Components and construction
- GlossaryActual dimension (pallet and lumber)An actual dimension is the measured size of a pallet or component at manufacture. Pallet spec sheets state component sizes as actual dimensions, for example a 5/8 × 3-1/2 × 40 in deckboard.
- GlossaryBlock (pallet)A block is a rectangular, square or cylindrical spacer between the decks of a block pallet. Most block pallets have 9 blocks in a 3 × 3 grid, and the block height sets the fork entry height.
- GlossaryBottom deck (pallet)The bottom deck is the lower layer of deckboards (or a perimeter, runner or panel base) on a double-face pallet. It spreads the load onto the floor, rack or conveyor and stabilizes the stringers or blocks.
- GlossaryBottom deck coverage (pallet)Bottom deck coverage is the percentage of a pallet's underside covered by bottom deckboards. A GMA-style 48 × 40 bottom deck covers about 45%, less than the top deck, to leave room for notches and pallet-jack wheels.
- GlossaryCenter block (block pallet)The center block is the middle block in the 3 × 3 grid of a nine-block pallet. It supports the middle of the deck and, on EPAL pallets, carries the producer, date and treatment marks.
- GlossaryChamfer (pallet)A chamfer is a bevel cut along the edge of a bottom deckboard, usually a lead board, so pallet-jack wheels can ride up and over it instead of hitting a square edge.
Last reviewed 2026-09-24. 268 words.