# Scaling Recipes in Excel: The Four Ingredients That Do Not Multiply

Multiplying every line by 2.5 works for flour and ruins the leavening, the salt, the pan, and the bake time. Here is the spreadsheet with CONVERT, fraction formatting, and the baker’s percentage that makes scaling exact.

---

- **Canonical URL:** https://dothecalculation.com/blog/templates/excel-recipe-scaling-and-unit-conversion
- **Category:** Templates
- **Author:** Do The Calculation Team
- **Published:** 2026-08-03
- **Reading time:** 10 min read
- **Publisher:** Do The Calculation (https://dothecalculation.com)
- **Methodology:** https://dothecalculation.com/methodology

---

## Most of a Recipe Scales Linearly

Going from four servings to ten is a factor of 2.5, and for flour, sugar, butter, eggs, and liquid that factor is exactly right. A spreadsheet does that arithmetic without fractions going wrong, which is reason enough to build one.

Four things do not scale linearly, and each ruins a dish in a different way.

Tool: [Try the recipe scaler](https://dothecalculation.com/calculators/recipe-scaler-calculator) — Scale a recipe between serving counts with the non-linear items flagged.

## The sheet

**Columns, with the scale factor in a named cell**
| Column | Header | Formula |
| --- | --- | --- |
| A | Ingredient | typed |
| B | Original quantity | typed |
| C | Unit | dropdown |
| D | Scales linearly? | Y or N |
| E | Scaled quantity | =IF(D2="Y", B2*Factor, B2*(1+(Factor-1)*0.6)) |
| F | Grams | =E2*XLOOKUP(A2&C2, Keys, GramsPerUnit, "") |

**The scale factor**

```
=TargetServings / OriginalServings
```
- Four servings to ten: 2.5
- Put it in one named cell so the whole recipe responds to a single change.
- A factor above about 4 usually needs the recipe rethought rather than scaled.

## The four that do not multiply

### Leavening

Baking powder and soda scale sub-linearly. At 2.5 times, multiplying the leavening by 2.5 gives a coarse crumb, a metallic taste, and a cake that rises then collapses. A common rule is to scale the increase rather than the whole quantity: apply about 60% of the extra the multiplier would add, then adjust across bakes.

Two teaspoons at a 2.5 factor becomes 5 teaspoons if multiplied straight and 3.8 teaspoons under that rule, since the increase of 3 teaspoons is reduced to 1.8. The formula in column E above applies exactly that rule to any row flagged as non-linear.

### Salt and strong spices

Salt in a dough scales linearly because it is a percentage of the flour. Salt in a sauce, and anything assertive such as cayenne, clove, or rosemary, scales sub-linearly, because perceived intensity does not track concentration. Scale to about 75%, taste, and adjust.

### Pan size

Pans scale by area, not by diameter. This is where most scaled bakes fail, because the volume goes up 2.5 times and the pan goes up in the wrong proportion.

**Pan area**

```
Round: =PI()*(Diameter/2)^2    ·    Rectangular: =Length*Width
```
- An 8-inch round is 50.3 square inches.
- Scaled 2.5 times, you need 125.7 square inches.
- That is a 12.7-inch round, or two 9-inch rounds at 63.6 each, which is 127.2 and close enough.

> **The pan check that prevents an overflow** — Add a column computing required area as OriginalArea × Factor, and a second listing the area of the pans you own. A simple lookup then tells you which pan or combination fits. Doubling a recipe into a pan of the same size is the most common scaling failure and the messiest.

### Cooking time

Time scales with the depth of the food, not with its quantity. Keep the depth the same by using more or larger pans and the time barely changes. Double the depth and the time can rise 50% or more while the temperature usually needs to come down 15 to 25 degrees Fahrenheit so the outside does not overcook.

Never scale a time in the spreadsheet. Flag it as a manual check instead, and note the target internal temperature, which is the only reliable measure across any batch size.

## Unit conversion with CONVERT

**The CONVERT function**

```
=CONVERT(number, "from_unit", "to_unit")
```
- =CONVERT(2, "lbm", "kg") returns 0.907
- =CONVERT(350, "F", "C") returns 176.7
- =CONVERT(1, "cup", "ml") returns 236.6
- Unit codes are case sensitive, which is the main reason it returns #N/A.

> **CONVERT cannot do cups to grams** — Cups measure volume and grams measure mass, so the conversion depends entirely on the ingredient. A cup of flour is about 120 g and a cup of honey is about 340 g. That needs a lookup table keyed by ingredient, not a unit conversion function.

**A starter density table, grams per US cup**
| Ingredient | Grams |
| --- | --- |
| All-purpose flour, spooned | 120 |
| Bread flour | 127 |
| Granulated sugar | 200 |
| Brown sugar, packed | 213 |
| Butter | 227 |
| Water | 237 |
| Milk | 244 |
| Honey | 340 |
| Cocoa powder | 85 |
| Rolled oats | 90 |

The flour row is why weighing matters. A cup of flour measured by scooping can be 145 g rather than 120, a 20% difference in the ingredient that determines the structure of the whole thing. Scaling a volume measurement scales that error too.

## Baker's percentage, which makes scaling exact

Bakers express every ingredient as a percentage of the flour weight, with flour always at 100%. Scaling then means choosing a new flour weight and recomputing, with no factor and no rounding drift.

**A basic bread formula**
| Ingredient | Percentage | At 500 g flour | At 1,250 g flour |
| --- | --- | --- | --- |
| Flour | 100% | 500 g | 1,250 g |
| Water | 68% | 340 g | 850 g |
| Salt | 2% | 10 g | 25 g |
| Yeast, instant | 1% | 5 g | 12.5 g |
| Total | 171% | 855 g | 2,137.5 g |

**Working backwards from a target dough weight**

```
Flour = TargetDoughWeight ÷ TotalPercentage
```
- For three 800 g loaves, target dough is 2,400 g.
- 2,400 ÷ 1.71 = 1,404 g of flour.
- Every other ingredient follows from its percentage of that.

Note that yeast is one of the non-linear ingredients in practice: a much larger dough ferments warmer through its own activity, so a straight percentage scaling can over-ferment. Reduce it slightly on large batches or shorten the proof.

## Displaying fractions

Cooks do not read 0.375 cups. Format the scaled quantity column with a custom number format of # ?/? for halves through eighths, or # ??/?? for finer fractions, and 0.375 displays as 3/8.

Round to something usable as well. =MROUND(E2, 0.125) snaps quantities to the nearest eighth of a cup, which matches the measuring spoons anyone actually owns. An exact 0.4167 cups is precise and unusable.

## What the spreadsheet cannot do

- Judge the result. Scaling factors above about four change the technique, not just the quantities, and a recipe developed for a home oven may not behave in a larger batch at all.
- Account for evaporation. A sauce reduced in a wider pan loses water faster, so a scaled sauce in the same pan ends up thinner and needs longer.
- Handle eggs. Two and a half eggs is not a quantity. Weigh them: a large egg is about 50 g without the shell, so scale by weight and use the closest whole number.
- Know your oven. Larger batches load an oven more, dropping the real temperature, and recovery time varies by oven.
- Adjust for altitude, humidity, or flour age, all of which change hydration and leavening more than a 10% scaling error would.
- Replace tasting. The non-linear rules above are starting points, and the correct amount of salt is the one that tastes right.

**Can I just multiply every ingredient by the scale factor?**

For flour, sugar, fat, liquid, and eggs, yes. For leavening, salt, and strong spices, apply only about 60% to 75% of the increase the multiplier would add. Never scale cooking time, and scale the pan by area rather than by dimension.

**How do I convert cups to grams in Excel?**

With a lookup table, not with CONVERT. Cups are volume and grams are mass, so the answer depends on the ingredient: a cup of flour is about 120 g and a cup of honey is about 340 g. Build a two-column table and use XLOOKUP.

**Why does my scaled cake sink in the middle?**

Usually too much leavening, which is the classic non-linear failure. It rises fast, the structure cannot hold it, and it collapses. Apply about 60% of the increase to baking powder and soda rather than the full multiplier, and check that the pan area was scaled too.

**How do I work out the right pan size?**

Compute the original pan area, multiply by the scale factor, and find a pan or combination matching the new area. An 8-inch round scaled 2.5 times needs about 126 square inches, which two 9-inch rounds provide at 127.

**What is baker's percentage?**

Every ingredient expressed as a percentage of the flour weight, with flour at 100%. It makes scaling exact: pick a flour weight and every other quantity follows. It also makes two recipes directly comparable, since hydration is visible as a single number.

**How do I display fractions instead of decimals?**

Custom number format # ?/? for eighths, or # ??/?? for finer fractions. Combine it with =MROUND(value, 0.125) so the underlying number is also a usable measurement rather than only displaying as one.

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_Source: [Do The Calculation](https://dothecalculation.com/blog/templates/excel-recipe-scaling-and-unit-conversion). Quote freely with attribution and a link to this page._