Egg Carton Dimensions: Cavity Depth, Footprint and Pallet Math

レオ・チャン著  | BonitoPak ライター | 成形パルプ製包装分野で20年以上の経験

Published: 21 August 2026   |   Last reviewed: 21 August 2026

A standard 12 count carton runs roughly 11.75 inches long by 4 inches wide, closing at about 2 to 2.25 inches for large eggs and 3 to 3.25 inches for jumbo. A 30 cell flat is close to 11.7 inches square. Case and pallet counts follow from those figures.

Egg carton dimensions are not the same thing as count. Count tells you how many eggs are in the pack. It tells you nothing about how much cold room the pack occupies, how many fit in a case, or how many cases go on a pallet. Those come from physical dimensions, and they are where packaging costs are actually decided.

This guide covers the measurements themselves, then works through the case and pallet arithmetic. If you are still choosing a format rather than specifying one, our guide to 卵パックのサイズと入数 covers that decision first.

Egg Carton Dimensions by Format

Use this egg carton size chart as working figures rather than as a standard. Cartons are made on tooling that varies between manufacturers, so treat them as the range you should expect and confirm exact numbers against your supplier’s drawing.

Two things stand out. Length stays remarkably consistent across 12 and 18 counts, because the row length is fixed at six cells. What changes is width, since an 18 count adds a third row rather than extending the carton. And the jumbo carton is not longer, it is taller.

Cavity Depth Follows Grade, Not Count

This is the specification buyers most often leave out of a quote, and it is the one that determines whether eggs sit securely.

USDA size classes are defined by minimum weight per dozen rather than by physical dimensions. Jumbo is 30 ounces per dozen, extra large 27, large 24, medium 21 and small 18, as set out in published wholesale pack format references. Heavier eggs are larger eggs, and larger eggs need deeper cells and a taller lid clearance.

So a carton described only as 12 count could be cut for large or for jumbo, and those are different molds producing different external heights. Specify the grade alongside the count and the supplier can give you real dimensions rather than a nominal range.

The practical failure mode is a lid that closes onto the shell rather than above it. That looks acceptable on a bench and produces breakage after a hundred miles of road vibration, because every point of lid contact becomes a stress point.

Egg Case Dimensions and What Actually Fits

Egg case dimensions are more standardized than carton dimensions, which makes the arithmetic easier.

A caution on published figures. Several widely circulated articles state that a 30 dozen case holds fifteen 30 cell trays, which would give 450 eggs rather than 360. Others describe a 15 dozen case as fifteen flats of twelve. Neither matches the specifications published by companies actually selling these cases, which consistently describe a 30 dozen case as twelve 30 cell flats and a 15 dozen case as six. Work from a supplier product specification rather than from a general article, including this one.

Note also that jumbo changes the flat as well as the carton. A jumbo filler flat holds 20 eggs rather than 30, so a case that takes twelve standard flats does not carry 360 jumbo eggs.

Working Out Your Egg Carton Pallet Configuration

The standard North American pallet is the GMA footprint at 48 by 40 inches. The method is the same regardless of case size.

Step one, cases per layer

Divide pallet length by case length, divide pallet width by case width, round both down, and multiply. Then repeat with the case rotated and keep whichever result is higher.

For a 15 dozen case at 12 by 12 inches: 48 divided by 12 gives 4, and 40 divided by 12 gives 3 after rounding down. That is 12 cases per layer. Rotating a square case changes nothing, which is one small advantage of a square footprint.

Step two, layers high

Take your maximum load height, subtract the pallet deck, and divide by case height. Working to roughly 95 inches of usable height above a five inch pallet, and a case height of 13.5 inches, gives 7 layers.

Step three, multiply out

12 cases per layer times 7 layers is 84 cases. At 180 eggs per case that is 15,120 eggs per pallet.

This is the calculation behind the TI and HI figures on pallet pattern sheets, where TI is cases per layer and HI is layers high, as explained in packaging references. Retail distribution centers expect those numbers on inbound pallets, and getting them wrong causes rejected shipments and repalletizing charges.

The Trap: Cube Utilization Is Not Pallet Efficiency

This is the most useful thing on the page, and it catches experienced buyers.

It is natural to optimize a case so it holds the maximum number of cartons with minimum wasted space inside. That is cube utilization, and maximizing it can lose you money.

The reason is that pallet fit depends on how case dimensions divide into 48 and 40, not on how efficiently the case is packed. A case that is beautifully full inside but divides badly into the pallet footprint wastes far more space on the pallet than it saved in the box. Published packaging worked examples show cases at 100 percent internal cube utilization shipping fewer units per pallet than cases at 93 percent, because the tighter case fitted only six per layer while the looser one fitted twelve.

The order of operations matters. Work out what divides cleanly into the pallet first, then design the case to those dimensions, then check how many cartons fit inside. Doing it the other way round optimizes the wrong variable.

Worth sanity checking the answer against a known figure. Standard egg cases are often quoted as loading somewhere in the region of 30 to 40 cases per pallet in general references, which reflects larger 30 dozen cases rather than the 15 dozen case worked through above. If your own calculation lands far outside the range you would expect for your case size, the usual cause is a rounding error or a forgotten clearance rather than a genuinely unusual configuration.

Clearances Everyone Forgets

Four allowances routinely get left out of a first calculation, and together they are enough to lose a layer.

• Internal versus external case dimensions. Corrugated board has thickness, and single wall C flute costs roughly five sixteenths of an inch across each dimension. Pack to internal dimensions, palletize to external.
• Assembly clearance. A theoretical zero clearance pack jams on a line. Allow an eighth to a quarter inch per dimension so flaps close and cartons load cleanly.
• Stretch wrap and corner boards. These add several millimetres per side to the finished load, which matters when you are within an inch of a rack opening.
• Trailer height. Most dry vans allow around 100 to 102 inches total including the pallet, and warehouse racking is often lower. Calculate to the lower of the two.

There is also weight. A pallet can be height limited or weight limited, and the real layer count is whichever comes first. Eggs are dense enough that a full height stack of cases can exceed a pallet weight budget before it runs out of vertical space.

自社の生産ラインで目にする光景

We cut tooling per project in Chashan Town, Dongguan, so external dimensions are something we set rather than something we look up. A few observations.

Forming process changes the wall, and the wall changes the dimensions

私たちの wet pressed cartons finish at a wall thickness of roughly 0.7 to 1.2mm, while dry pressed trays finish at roughly 2.5 to 3.0mm. At the same internal cell geometry those produce different external dimensions. It is a small difference per carton and a meaningful one across a stack of fifteen inside a case.

Nesting is a tooling decision that changes your pallet count

How well flats nest is governed by the draft angle on the cell walls when the mold is cut. Too little draft and trays lock together and slow the packing line. Too much and stack height grows, which can cost you a layer on the pallet. We settle draft before cutting tooling because it cannot be adjusted afterwards without a new mold.

Check pallet fit at sample stage, not after production

Sample molds run in about seven days and production molds follow around eight days after geometry approval, with minimums from 1,000 pieces. That gap exists so real parts can be measured and stacked before the production tool is committed. Once external dimensions come off a production mold, changing them means new tooling. Our custom egg tray page sets out what is adjustable at that stage, and the same nesting logic applies to stacked 成形パルプトレイ.

One recurring request worth flagging. Customers sometimes ask for a thinner wall purely to gain a pallet layer. That trade is available, but wall section is carrying the stacking load, and the eggs at the bottom of a seven layer pallet are relying on it. The materials side of that decision is covered in our article on what egg cartons are made of.

これを実践に活かす

Specify grade alongside count on every quote request, and ask for external dimensions rather than a size name. Those two habits eliminate most fit surprises before they reach production.

Then work the logistics in the right order. Establish what case footprint divides cleanly into 48 by 40, design the case around that, and only then check how many cartons fit inside it. Deduct board thickness, assembly clearance, wrap and a realistic height limit before you commit, and check whether weight or height binds first.

で ボニートパック we confirm external dimensions on physical samples before a production mold is cut, because a carton that fits the eggs but not the case is an expensive thing to discover at the first shipment. Sending your case and pallet targets alongside the egg grade lets both be designed together rather than sequentially.

著者について

Leo Chan is the founder of BonitoPak and has spent more than 20 years in molded pulp packaging, working with over 500 brands moving from plastic and foam to fiber based formats. BonitoPak manufactures molded pulp packaging at its facility in Chashan Town, Dongguan, Guangdong, running both wet pressing and dry pressing lines across six pulp systems, with in house mold design and tooling. The dimensional guidance here reflects tooling work on that line alongside published case specifications and pallet loading references, which should always be confirmed against your own supplier drawings.

よくある質問

Q: Why does every egg carton size chart show different numbers?

A: Cavity depth and wall section differ by tooling, and forming process changes wall thickness. A wet pressed carton and a dry pressed one at the same count will not have identical external dimensions.

Q: Does egg grade change the carton footprint?

A: Rarely the footprint, usually the height. Cell diameter and depth grow with grade, which pushes closed lid height up. Jumbo cartons are noticeably taller than large at the same length and width.

Q: How do I calculate eggs per pallet myself?

A: Divide pallet length and width by case dimensions to get cases per layer, divide usable height by case height for layers, multiply the two, then multiply by eggs per case. Round every division down.

Q: What height should an egg carton pallet configuration allow?

A: Most dry vans allow around 100 to 102 inches total including the pallet deck. Deduct roughly five inches for the pallet, then leave margin for stretch wrap and any load top sheet.

Q: Can I change egg carton dimensions after tooling is cut?

A: No. External dimensions come from the mold, so any change means new tooling. This is why pallet fit should be checked at the sample stage rather than after the first production run ships.