Costing in a notebook, a spreadsheet or an app

All three can cost a recipe correctly. The difference is what happens when a price changes. In a notebook you redo every recipe that uses that ingredient by hand. In a well-built spreadsheet you change the price in one cell and every recipe updates. An app does the same without you building any formulas, in exchange for a fee and some dependence on it. Pick the one you will actually keep current: costs based on prices from three months ago are wrong wherever they live.

The notebook

It is where almost everyone starts, and it has real strengths.

What it does well

• It is always to hand, in the kitchen or at the market.
• It costs nothing and never crashes.
• It makes you do the sums, so you understand where every number comes from.

What it misses

• When an ingredient goes up, you have to find every recipe that uses it and recalculate each one. In practice, nobody does.
• Addition mistakes stay put. Nobody re-checks a sum written two months ago.
• Comparisons are hard: which product earns most, how a cost has changed since January.
• It gets splashed, lost, or left at home.

A notebook works with three or four products and stable prices. Beyond that it becomes a record of old costs.

The spreadsheet

Excel or Google Sheets fix the notebook's main problem, if you set them up properly.

What it does well

• Formulas do the arithmetic without addition mistakes.
• If prices live on one ingredients tab and the recipes pull from it, one price change updates everything.
• It is free or nearly free, and you can shape it to your business.

What it misses

• It is only as good as its structure. If you typed the price of butter into each recipe instead of pulling it from a list, you are back to the notebook problem.
• Units. You buy oil by the litre, the recipe says "half a cup", and the sheet cannot convert unless you teach it. This is the most common source of errors, covered in units and conversions for food costing.
• Formulas break. Insert a row or delete a cell and a product's cost goes wrong without anyone noticing.
• It is awkward on a phone, and the shop is where you see the prices.
• Usually only one person understands how it works.

The app

A costing app does the setup work for you that a spreadsheet makes you do by hand.

What it does well

• Ingredients live in one list: change a price and every recipe that uses it recalculates.
• It converts purchase units into recipe units.
• It usually works well on a phone, so you can record a price the moment you pay it.
• Some keep a price history, which shows how a cost has moved over time.

What it misses

• You still have to enter the prices. No app knows what you paid at the cash and carry yesterday.
• There may be a monthly fee, and learning it takes time.
• You depend on it. Before choosing one, check whether you can export your data.
• If it does not include packaging, labour and energy, it gives you an ingredient cost, not a loaded cost.

For which other parts of the business are worth moving onto your phone first, see digital tools for small food businesses.

What each one misses, side by side

Worked example: butter goes up

You make brownies, granola and shortbread. Butter was $2.80 for a 250 g block and this week it is $3.50.

• Before: 2.80 ÷ 250 = $0.0112 per gram
• Now: 3.50 ÷ 250 = $0.0140 per gram
• Difference: $0.0028 per gram

For the brownies: 8,000 g × $0.0028 = $22.40 a month, or 200 × 0.0028 ÷ 16 = $0.035 more per brownie.

In total, 22.40 + 12.60 + 17.50 = $52.50 a month of extra cost from one ingredient. If your costing still says $2.80, your margins look unchanged on paper and that $52.50 disappears without you seeing it. Add a rise in chocolate or eggs and it adds up quickly.

What it takes to fix in each tool:

• Notebook: three recipes to redo, if you remember which ones use butter.
• Spreadsheet with the price typed into each recipe: three cells to change, and it is easy to miss one.
• Spreadsheet with an ingredients list, or an app: one change, three recipes updated.

And when butter comes back down, the same job in reverse.

The real problem is keeping prices current

Any of the three gives you a correct cost on the day you fill it in. The difference is how much effort it takes to keep it right. Whatever tool you use, these help most:

• Record the price when you buy, per base unit (per kilo, per litre), not "when I get a minute". How to track ingredient prices across shops has a simple method.
• Keep the receipt, or a photo of it, the same day.
• Have a rule for when to recalculate. It is in how often to update your costs.

How to choose

• Few products, stable prices, time to check: notebook, with a monthly review.
• Several products sharing ingredients, and you are comfortable with formulas: spreadsheet, with one ingredients tab that every recipe reads from.
• Many recipes, prices that move every week, or very little time: app.

Whichever you pick, the method is the same: loaded cost per unit, with ingredients, packaging, labour, energy and waste. It is laid out step by step in how to calculate the cost of a food product.

Do it with the calculator

If you want to try before deciding, the food cost calculator is free: enter one recipe with what you paid for each ingredient and it returns the cost per unit and the price for your margin. It is a quick way to check what your notebook or spreadsheet says today.