What the thickness factor is and why pizzerias use it
The thickness factor is dough weight divided by pizza area: ounces of dough per square inch of pizza. Tom Lehmann, who ran the American Institute of Baking's pizza programme and answered operators' formula questions for decades, popularised it as the way to move a crust between sizes without changing how it eats. Fix the factor and every size of pizza on your menu has the same crust; change the factor and every size changes together.
The reason a factor is needed at all is that dough weight tracks area, and area is quadratic in diameter. Going from a 12-inch to a 16-inch pizza is a 33% increase in diameter but a 78% increase in area, so a shop that adds a third more dough will serve a noticeably thinner large pizza than its medium. Operators who scale by diameter get complaints about the large; operators who scale by area do not.
The factor is also how you carry a recipe across shapes. A pan does not care about diameter — it has a base area, and multiplying that area by the same factor gives a ball weight that behaves like your round pizzas. That is what makes the method useful for Sicilian trays, half-sheet pans, square Detroit pans and round pizzas from the same dough.
Two things the factor does not capture. It says nothing about the dough formula — hydration, oil, sugar and fermentation all change how a given loading eats. And it assumes the dough is stretched to the stated finished size. Two cooks working the same 14 oz ball to 13 inches and 15 inches are producing different pizzas from identical numbers, which is why shops that care about consistency mark their benches or use a rim ring.
The formula, and how to measure your own factor
Start from a pizza you already make well. Weigh the dough ball before proofing, note the diameter you stretch it to, and divide:
TF = dough weight in ounces ÷ area in square inches
Round area is π(d/2)², so a 14-inch pizza is π × 7² = 153.94 in². A 16 oz ball on that pizza gives 16 ÷ 153.94 = 0.1039 oz/in². That number is now your crust, expressed in a form that transfers.
Going the other way, dough weight = TF × area. For a round target, work out π(d/2)² and multiply. For a rectangular or square pan, area is simply length × width measured at the base of the pan, not at the rim — sloped-side pans can be a full inch narrower at the bottom, and using the rim measurement overloads them.
There is a shortcut worth knowing when you only need to move between two round sizes: new weight = old weight × (new diameter ÷ old diameter)². Moving 16 oz from 14 inches to 16 inches gives 16 × (16/14)² = 16 × 1.3061 = 20.90 oz. The factor cancels out, which is a useful check on any answer this calculator gives you.
Metric users can work in grams per square centimetre. Multiply the imperial factor by 28.3495 g/oz and divide by 6.4516 cm²/in², which comes to multiplying by 4.3941. A 0.10 oz/in² crust is 0.4394 g/cm². The calculator reports both, and every length and weight input accepts metric.
Worked example: taking a 14-inch crust to 16 inches and to a Sicilian pan
Your 14-inch pizza uses a 16 oz ball and the crust is exactly what you want. You are adding a 16-inch size and an 18 × 13 inch Sicilian pan to the menu.
- Reference area. π × (14 ÷ 2)² = π × 49 = 153.94 in².
- Thickness factor. 16 ÷ 153.94 = 0.10394 oz/in².
- Target area, 16-inch round. π × (16 ÷ 2)² = π × 64 = 201.06 in².
- Dough ball, 16-inch. 0.10394 × 201.06 = 20.90 oz (592 g). Cross-check with the shortcut: 16 × (16/14)² = 16 × 256/196 = 20.90 oz.
- Target area, Sicilian pan. 18 × 13 = 234 in².
- Dough ball, Sicilian at the same crust. 0.10394 × 234 = 24.32 oz (690 g).
That last number is the honest answer at the same thickness, but most Sicilian and Detroit formats are deliberately thicker. Push the factor to 0.15 for the pan only and the ball becomes 0.15 × 234 = 35.1 oz (995 g). Notice what has happened: the round sizes still share one factor, and the pan carries its own. That is normal practice — a shop typically runs two or three factors, one per style, rather than one for the whole menu.
One more check that catches errors. Compare the areas rather than the diameters: 201.06 ÷ 153.94 = 1.306, so the 16-inch pizza has 30.6% more area and needs exactly 30.6% more dough. If your answer does not have the same ratio as the areas, the arithmetic went wrong somewhere.
Reading the factor: what number goes with what style
Treat the thickness factor as a style setting. As rules of thumb used across the trade, a cracker-thin bar pie sits around 0.06-0.08 oz/in²; a thin New York slice runs roughly 0.085-0.10; a standard hand-tossed crust around 0.10-0.12; a thicker American-style crust 0.12-0.14; and pan, Sicilian and Detroit formats from 0.15 upward, sometimes past 0.20 for a deep pan. These are starting points for a first test bake, not standards — every shop lands on its own number, and the same figure eats differently at 60% hydration than at 70%.
Two facts shape how you should adjust. First, the factor is proportional to dough weight at fixed size, so a 10% change in the factor is a 10% change in the ball. That makes it easy to dial in: bake at your current number, decide the crust wants to be a bit thicker, add 8% and bake again. Second, the crust is thicker than the factor implies at the rim, because most of the stretched dough migrates outward. A pizza is not a slab of uniform depth, and two crusts at the same factor can have very different rims depending on how they are opened.
Watch out for the difference between a finished-size factor and a pan-size factor. If you measure your reference from the pan the dough goes into, but stretch the target pizza past the pan edge or bake it on a deck, your two numbers describe different things. Pick one convention — finished pizza diameter is the more useful for deck ovens, pan base area for pans — and stay with it.
Finally, the factor governs portioning, not fermentation. A 20.9 oz ball and a 16 oz ball off the same dough need the same schedule, but a change in ball size does change how quickly the ball cools in a fridge and how long it takes to come to room temperature, which matters on a two- or three-day cold ferment. The desired dough temperature calculator is the tool for keeping that side consistent, since pizza doughs are usually mixed to a deliberately low dough temperature so the trays chill quickly.
Dough ball weight by pizza size and thickness factor
| Diameter | Area (in²) | TF 0.085 (thin) | TF 0.105 (standard) | TF 0.125 (thick) | TF 0.150 (pan) |
|---|---|---|---|---|---|
| 10 in | 78.54 | 6.68 oz | 8.25 oz | 9.82 oz | 11.78 oz |
| 12 in | 113.10 | 9.61 oz | 11.88 oz | 14.14 oz | 16.96 oz |
| 14 in | 153.94 | 13.08 oz | 16.16 oz | 19.24 oz | 23.09 oz |
| 16 in | 201.06 | 17.09 oz | 21.11 oz | 25.13 oz | 30.16 oz |
| 18 in | 254.47 | 21.63 oz | 26.72 oz | 31.81 oz | 38.17 oz |
| 20 in | 314.16 | 26.70 oz | 32.99 oz | 39.27 oz | 47.12 oz |
Multiply any ounce figure by 28.35 to get grams. Note how the same factor produces a ball four times heavier at 20 inches than at 10 inches, because the area is four times larger.
Mistakes that put a dough ball off
- Scaling by diameter instead of by area. The error that started the whole method. Adding 14% of dough for a 14% bigger diameter leaves the larger pizza noticeably thinner.
- Measuring a sloped pan at the rim. Pan area is the base, where the dough actually sits. A tapered 12-inch pan can have a 10.5-inch base, which is 23% less area.
- Mixing finished-size and pan-size conventions. Decide whether your factor refers to the pizza you serve or the pan you press into, and use the same one on both sides of the calculation.
- Weighing the ball after proofing. Scale the dough before the final proof. Fermentation loss and skin drying both change the number, and the reference and target must be weighed at the same stage.
- Assuming one factor covers the whole menu. Pan, Sicilian, Detroit and hand-tossed styles all have their own loading. Running one factor across styles makes the pan pizzas thin and the thin pizzas heavy.
- Ignoring the rim. A pizza opened with a thick cornicione carries proportionally less dough in the centre than one pressed flat to the edge, even at an identical factor.
- Forgetting to re-check after a formula change. Raising hydration by five points makes the same weight of dough spread further and bake lighter. Re-measure the factor after any real change to the dough.
Key terms
- Thickness factor (TF)
- Dough weight per unit of pizza area, conventionally ounces per square inch. The number that stays fixed when you change size.
- Dough loading
- The same idea expressed in whatever units you prefer — grams per square centimetre is the common metric form.
- Scaling
- Weighing dough into individual portions. In pizza production the scaled weight is the ball weight before the final proof.
- Cornicione
- The raised outer rim of a pizza. It absorbs a disproportionate share of the dough, which is why two pizzas at the same thickness factor can have very different centres.
- Detroit and Sicilian pans
- Rectangular formats, typically pressed and proofed in an oiled pan. Both usually run a much higher thickness factor than a round hand-tossed pizza.
Where portioning sits among the other pizza numbers
Thickness factor answers only the portioning question. The rest of a pizza dough is baker's percentage work: flour at 100%, water somewhere between 58% and 70% depending on style and oven, salt around 2%, oil 0-3%, and a very small yeast dose for a long cold ferment. Two of those numbers interact with this page. Hydration changes how far a given ball stretches, so a factor measured on a 62% dough will feel light on a 70% one. And yeast dose has to be matched to the length of the cold ferment, which the yeast conversion calculator helps with when you are converting a formula between fresh, active dry and instant, or trimming a dose for a three-day proof.
For naturally leavened pizza, the levain replaces the yeast and the portioning logic is unchanged. Size the levain with the sourdough levain build calculator, then account for its flour and water in your hydration using the sourdough starter hydration calculator — a 20% levain on a pizza dough shifts hydration by several points, and pizza dough is a style where a few points changes how the skin opens.
Two limits on the method. It is a linear model: it assumes dough weight and area move together at a constant ratio, which holds well across the range of sizes a shop actually sells but drifts at extremes, because the rim takes a fixed-ish share of dough regardless of size, so very small pizzas end up proportionally rimmier than the factor implies. And it says nothing about bake. A 0.15 factor in a 900 °F wood oven is not the same product as 0.15 in a 500 °F home oven, and no portioning number will bridge that gap. Use the factor to make your sizes consistent with each other, and use test bakes to decide what the factor should be.