A pizza box should measure slightly more inside than the pizza, and the size printed in a catalogue often does not tell you which dimension it refers to. One supplier's "12 inch box" holds a 12-inch pizza, another's measures 12 inches inside and fits an 11-inch pizza comfortably, and a third quotes outside dimensions. Compare internal millimetres, not labels. Below are the clearance rules, an indicative chart in inches and centimetres, depth by pizza style and the tolerances that decide whether a box works on a busy Friday night. Board, print and food-contact choices are covered on the main custom printed pizza boxes page.
How much bigger than the pizza should the box be?
The internal size of a pizza box is commonly about 0.5-1 inch (roughly 1.3-2.5 cm) larger than the nominal pizza diameter, or 1-2 cm on metric sizes. That clearance absorbs the natural variation of hand-stretched dough and leaves room to slide the pizza in from a peel or screen without catching the crust.
Less clearance than that, and a pizza that has been stretched a little wide will ride up the walls, the crust edge will break, and toppings will touch the lid. Much more clearance, and the pizza slides around in transit, cheese drifts to one side, and the empty space cools the product faster. Operators who cut the pizza in the box also need enough room to move a wheel or rocker blade around the edge.
Where you sit in that range depends on how consistent your pizzas are. A pressed or machine-formed base varies little and can live with the lower end; a hand-stretched Neapolitan-style pizza with a puffy cornicione varies more and needs the upper end.
Pizza box size chart (inches and centimetres)
The table below gives indicative internal sizes for the most common nominal pizza diameters. Treat it as a starting point for samples, not a specification.
| Nominal pizza | Pizza diameter (approx.) | Indicative internal box size | Typical internal depth (standard crust) |
|---|---|---|---|
| 10 inch | 25-26 cm | 10.5-11 in / 27-28 cm | 1.5-1.75 in / 3.8-4.5 cm |
| 12 inch | 30-31 cm | 12.5-13 in / 32-33 cm | 1.5-1.75 in / 3.8-4.5 cm |
| 14 inch | 35-36 cm | 14.5-15 in / 37-38 cm | 1.75-2 in / 4.5-5 cm |
| 16 inch | 40-41 cm | 16.5-17 in / 42-43 cm | 1.75-2 in / 4.5-5 cm |
| 18 inch | 45-46 cm | 18.5-19 in / 47-48 cm | 2 in / 5 cm |
| 26 cm | 26 cm | 27-28 cm | 3.5-4 cm |
| 30 cm | 30 cm | 31-32 cm | 3.5-4 cm |
| 33 cm | 33 cm | 34-35 cm | 4 cm |
| 36 cm | 36 cm | 37-38 cm | 4-4.5 cm |
| 40 cm | 40 cm | 41-42 cm | 4-5 cm |
| Party / al metro 40 x 60 cm | 40 x 60 cm rectangle | approx. 41-42 x 61-62 cm | 4-5 cm |
US operators work mostly in 10, 12, 14, 16 and 18-inch sizes; continental European pizzerias commonly use 26, 30, 33 and 36 cm, with 40 cm and 40 x 60 cm party formats for sharing. UK operators use both systems: delivery chains tend to work in inches, independent and Italian-style pizzerias often in centimetres.
Why catalogue sizes disagree
Box sizes are labelled in at least three ways, and catalogues rarely say which:
- By the pizza the box is meant for ("box for 33 cm pizza").
- By the internal dimension ("33 x 33 cm box"), which suits a slightly smaller pizza.
- By the external dimension, which is larger than the internal by roughly two board thicknesses plus fold allowance.
A box labelled "33 x 33" can therefore suit anything from a 30 cm to a 33 cm pizza depending on the supplier. When you compare quotations or switch suppliers, compare internal length, width and depth in millimetres, and send a current box if you want a match.
Internal vs external dimensions
The internal dimension decides whether the pizza fits; the external dimension decides whether the box fits your delivery bags, hot-holding shelves, warming cabinets and storage. The gap between the two is set mainly by board thickness.
| Board | Typical caliper | Approximate external over internal (each direction) |
|---|---|---|
| E-flute | ~1.1-1.8 mm | ~4-7 mm |
| B-flute | ~2.5-3.2 mm | ~6-10 mm |
These are approximate, because the exact allowance depends on the die design and how the walls are folded (double-thickness walls add more). The practical consequence: if you move a size from E-flute to B-flute for strength, keep the internal size and check that the slightly larger box still fits your bags and shelves. The trade-offs between the two boards are covered in E-flute vs B-flute pizza boxes.
How deep should a pizza box be?
For a standard thin or medium crust pizza, an internal depth of about 3.5-5 cm (roughly 1.5-2 inches) is typical; the box should clear the highest topping or crust edge by around 1 cm so the lid does not touch the cheese, even when a few boxes are stacked on top.
Depth guidance by style:
| Style | Typical internal depth |
|---|---|
| Thin crust, Roman-style | 3-4 cm (about 1.25-1.5 in) |
| Standard / New York / medium crust | 3.5-4.5 cm (about 1.5-1.75 in) |
| Neapolitan with high cornicione | 4-5 cm (about 1.75-2 in) |
| Heavily topped or stuffed crust | 4.5-5 cm (about 2 in) |
| Deep-pan, Detroit, Sicilian | 5-7 cm or more (about 2-3 in) |
Lid sag is the reason for the extra margin. A lid that clears the pizza in a single box can drop several millimetres under the weight of two or three filled boxes, especially once steam has softened the board. Depth that is too generous costs board and leaves headspace that cools the pizza, so test before you add more.
Tolerances: what variation to expect
Three sources of variation stack up in a pizza box: the pizza, the box and the board.
- Pizza: hand-stretched bases commonly vary by a centimetre or more between staff and shifts; ovals and irregular edges are normal.
- Box: die-cut corrugated is produced to tight tolerances, typically within a millimetre or two on cut dimensions, but folding position and board caliper add small variations to the erected box.
- Board: caliper varies with flute, liner grammage and, after storage in a humid kitchen, moisture content; flute can be slightly crushed during printing.
Of the three, the pizza is usually the largest variable, which is why clearance matters more than fractions of a millimetre in box tolerance. Before fixing dimensions, measure 20-30 pizzas from a normal service across several staff members and size the box to the upper end of that range plus a small margin. Final dimensional tolerances for a production run are agreed at quotation and technical review.
Rectangular, pinsa and slice box sizes
Non-round formats are sized to the dough or tray, not to a diameter. A box designed for one format rarely works well for another, so specify each separately.
| Format | How to size | Notes |
|---|---|---|
| Party pizza / al metro (e.g. 40 x 60 cm) | Tray or dough size + about 1-2 cm each way | Long span needs stiffer board, usually B-flute; check car and bag fit |
| Half-metre or long formats (e.g. 30 x 50 cm, 25 x 50 cm) | Tray size + clearance | Used for sharing and "pizza al metro" menus |
| Pinsa (oval or rectangular, Roman-style) | Longest and widest point + about 1-2 cm | Commonly around 30-35 cm long; measure your own pinsa as sizes vary |
| Detroit / Sicilian / pan | Pan internal size + clearance; deeper walls | Square or rectangular pans; check depth carefully |
| Calzone | Folded length and width + clearance; extra depth | Narrow box; steam venting matters |
| Slice box (single slice) | Slice length and width of your largest slice | Triangular wedge or small square box |
| Personal / mini pizza (e.g. 7-9 inch, 18-22 cm) | As round pizzas | Often E- or F-flute; print surface more important than strength |
If you run both round and rectangular pizzas, avoid the temptation to use a large round box for small rectangular products: excess space lets the product slide and cool.
How many sizes should a pizza business stock?
Most operators manage with three or four round sizes plus one specialty format. Every additional size means another die, another stock line, more storage space and, for printed boxes, more artwork and plate management.
A practical approach for chains is to fix the menu sizes first and then rationalise boxes, rather than the other way round. Where two pizza sizes differ by only an inch or two, one box can sometimes serve both if the clearance on the smaller size stays acceptable; test it with real product before cutting a SKU. Fewer sizes also make full-pallet and full-run ordering easier, which affects unit price; see packaging MOQ explained.
Checking fit with delivery bags and equipment
Before approving dimensions, confirm the external size against everything the box has to fit into:
- Insulated delivery bags (single, double and multi-box bags), including stack height when the bag is closed.
- Hot-holding shelves, heated cabinets and pass-through windows.
- Storage shelving for flat stock and pre-folded stacks.
- Courier and aggregator bags if third-party delivery is used.
- Counter carry-out bags if pizzas leave in paper bags; custom printed takeaway bags can be sized around your largest box.
Sizing checklist for a pizza box quotation
Send the following to get a box that fits first time:
- Nominal pizza sizes on your menu and the measured diameter range of real pizzas.
- Pizza style and maximum height (crust and toppings), for depth.
- Required internal length, width and depth in millimetres, or a current box to match.
- Any maximum external size set by bags, shelves or warming cabinets.
- Board preference, if known, since it changes the external size.
- Special formats (party, pinsa, slice, calzone) with tray or product dimensions.
Use these with the packaging RFQ guide, or return to the custom printed pizza boxes page for the full specification, and send your sizes for a quotation.
For a quick internal and external size from your pizza diameter, try the pizza box size calculator. It applies the clearance rules on this page.