Cost per unit is everything you spent on a batch divided by the units that actually came out ready to sell, plus whatever each unit needs on its own, like packaging. The formula is short: batch cost ÷ real yield + packaging per unit. The mistake is almost always in the divisor. If you divide by what the recipe promised instead of what you actually got, your cost comes out lower than it really is.
The formula
cost per unit = (batch cost ÷ real units) + packaging cost per unit
Two parts, because there are two kinds of spending:
- Per-batch costs: ingredients, the energy for the cook, your prep time. It makes no difference whether you get 17 jars or 20: the batch costs the same.
- Per-unit costs: jar, lid, label, bag. One fewer unit means one fewer jar.
First divide the batch costs by the real yield. Then add the per-unit costs.
What goes into the batch cost
Add up everything you spend to produce the full batch:
- Ingredients. Each one at its price per gram, millilitre or unit, based on what you paid. If you buy by the package and only use part of it, how to cost an ingredient you buy by the package shows how to price the part you use.
- Energy and water for the batch. What that cook uses. An honest estimate is enough.
- Your time. Hands-on hours for the batch times the rate you pay yourself.
If one batch uses ingredients bought in different places at different prices, use the price of the stock you are actually using, not an average from memory.
How to measure the real yield
Yield is how much sellable product you have at the end. It is not what the recipe says, and it is not your best ever batch.
- If you sell by the unit: count the units that pass your quality check. Broken, undersized and tasted ones do not count.
- If you sell by volume: measure the final amount after cooking and straining, and turn it into full containers.
- If you sell by weight: weigh the finished product, not the raw ingredients.
Do it over three batches in a row and use the average. What moves yield most: water that cooks off, what stays in the pan and the sieve, and the real size of your portions. The guide on what recipe yield is and how to measure it has the full method.
Worked example: jars of strawberry jam
You make strawberry jam in 250 g jars. Your recipe says a batch makes 20 jars.
Batch ingredients
| Ingredient | Working | Cost |
|---|---|---|
| Strawberries | 3 kg × $4.00 | $12.00 |
| Sugar | 2 kg × $1.50 | $3.00 |
| Lemons | 3 × $0.50 | $1.50 |
| Pectin | 1 sachet | $1.50 |
| Total ingredients | $18.00 |
Other batch costs
- Energy for the cook: $1.50
- Your time: 1.75 hours × $18 = $31.50
Batch cost: 18.00 + 1.50 + 31.50 = $51.00
Real yield. The jam reduces more than the recipe expects. You fill 17 jars, plus a half jar you keep.
Batch cost per jar: 51.00 ÷ 17 = $3.00
Packaging per jar: jar and lid $0.85 + label $0.15 = $1.00
Cost per unit: 3.00 + 1.00 = $4.00 per jar
Now the version using the recipe's yield:
- 51.00 ÷ 20 = $2.55
- 2.55 + 1.00 = $3.55 per jar
The difference is $0.45 a jar. At 80 jars a month, that is $36 a month you think you are making and are not. And if you price by applying a margin to $3.55, the whole price inherits the error.
Mistakes that hide the real cost
- Dividing by the recipe. As you saw, the cost drops on paper and not in real life.
- Putting packaging in the batch. When the yield changes, you end up counting jars you did not use, or leaving out ones you did.
- Forgetting time and energy. Ingredient cost per unit is only part of the picture. It is good for comparing recipes, not for pricing.
- Rounding too early. Do the divisions with all the decimals and round to the cent at the end.
- Costing from your best batch. If you once got 20 jars and usually get 17, the honest number is 17.
From cost per unit to loaded cost
Cost per unit tells you what each jar costs to make. It does not yet tell you what each jar sold costs. Two things are still missing:
- Sales waste: jars that do not sell, get damaged or go out as samples. If you sell 15 of every 17, those 15 have to pay for all 17.
- Costs outside the batch: the market stall, your phone, insurance, spread over what you produce in the month.
Adding those gives you the loaded cost per unit, which is the number to price from. The full step-by-step method is in how to calculate the cost of a food product.
When the batch size changes
When you double a batch, the ingredients double, but your time and energy almost never do. That is why cost per unit usually falls with bigger batches, until you hit the limit of your pan or of what you can sell before it spoils. Every time you change batch size, measure the yield again: a wider pan reduces jam faster and can change how many jars you fill.
Do it with the calculator
Put the batch ingredients, energy, your time, the real yield and the packaging per unit into the food cost calculator, and it gives you the cost per jar and lets you change the yield to see how much it moves the result.
Frequently asked questions
What if every batch yields a different amount?
That is normal. Record the yield of three to five batches in a row and use the average. If the spread between batches is wide, the problem is in the recipe or the portioning, and it is worth fixing before you cost anything.
Does packaging go into the batch cost or per unit?
Per unit. Each jar or bag is used once per product sold, so you add it after dividing the batch. If you put it in the batch and the yield drops, you end up counting packaging you never used.
How do I work out cost per unit if I sell by weight?
The same way, but the unit is the kilo or the 100 grams. Weigh what is ready to sell and divide the batch cost by those kilos.
Is cost per unit my real cost?
It is the base. To get the real cost you still need to add the waste from what does not sell and spread the costs that sit outside the batch. That total is the loaded cost.