How the plate cost math works
Every ingredient line goes through the same three steps. First, divide the case price by the number of units in the case to get the price per pound, per each, per quart or whatever unit you count in. Second, divide that by the yield to get the cost of a usable unit. Third, multiply by the amount on the plate.
Plate cost is the sum of those lines plus a Q factor for the small stuff. The suggested price is plate cost divided by your target food cost percentage, and food cost percentage at your current price is plate cost divided by menu price.
| Step | Formula |
|---|---|
| Price per unit | case price ÷ units per case |
| Usable cost per unit | price per unit ÷ yield % |
| Line cost | usable cost per unit × units used |
| Plate cost | sum of lines × (1 + Q factor %) |
| Price at target | plate cost ÷ target food cost % |
How to use the calculator
- Pull the most recent invoice for each ingredient. Use what you actually paid, including any delivery or fuel surcharge you can tie to that product.
- Pick one unit per ingredient and stick to it. If you buy chicken by the 40-pound case and portion it by weight, count in pounds.
- Enter a yield for anything you trim, peel, bone or cook down. If you don't know it, do a yield test (below). Use 100 for items with no loss, like dry rice measured before cooking.
- Enter the amount that goes on one plate, in the same unit.
- Add a Q factor and your target food cost. Enter the current menu price if you have one.
- Download the CSV and keep it with your recipe card so the next re-cost takes minutes.
A worked example
Take a chicken rice bowl with three main components, using the sample numbers already in the calculator.
Chicken thighs cost $68 for a 40-pound case, so $1.70 a pound. After trimming and cooking, only 78 percent of the raw weight is servable, which puts the real cost at $2.18 per usable pound. Half a pound on the plate costs $1.09.
Rice at $32 for 25 pounds is $1.28 a pound dry. A 0.18-pound portion costs about 23 cents. Broccoli at $36 for 20 pounds is $1.80 a pound, but only 65 percent is usable florets, so each usable pound costs $2.77 and a quarter-pound portion costs 69 cents.
Ingredients total about $2.01. A 5 percent Q factor adds 10 cents, for a plate cost of roughly $2.11. At a 30 percent target, the price works out to about $7.04, and at the current $18 menu price the food cost is under 12 percent. That gap is a prompt to ask a question, because a bowl that cheap to make probably has room for a larger portion, a better protein, or a lower price that drives more orders. The number tells you where to look; it doesn't make the call for you.
Running a quick yield test
Yield is where most plate costs go wrong, and it takes twenty minutes to measure. Weigh a full case or a fair sample as it arrives. Prep it the way your recipe says, then weigh what's usable. If it's cooked, weigh it after cooking and resting. Usable weight divided by starting weight is your yield.
Do the test twice on different deliveries and average the results. Write the number on the recipe card and in the calculator. When a new prep cook joins, repeat it, because trim habits change from person to person.
Mistakes that throw off plate cost
The most common one is costing the recipe instead of the plate. If the recipe calls for four ounces of protein but the line is serving five, your cost is off by 25 percent on the biggest line. Check portions on a scale during a real service.
The second is forgetting the things that go out with the plate: the side sauce in a ramekin, the lemon wedge, the bread basket, the to-go container. Either add them as lines or make sure your Q factor covers them.
The third is leaving old prices in place. A plate costed eighteen months ago is a guess. Put a "last costed" date on every recipe card and look at it when you review the menu.
Where plate cost fits
Plate cost tells you what one item should cost. Your actual food cost for the month also includes waste, theft, staff meals, comps and over-portioning, which is why actual food cost usually runs a few points above the theoretical number from your recipe cards. If the gap gets wide, look at receiving, storage and portion control before you change prices. The prime cost calculator puts food cost next to labor so you can see the whole picture.
Frequently asked questions
What is a good food cost percentage for a restaurant?
There is no single right number. Plenty of full-service independents plan for somewhere around the high 20s to mid 30s, but a steakhouse, a pizza shop and a fine-dining room will land in different places. Set the target from your own prime cost and profit goals, then cost each plate against it.
What is yield percentage?
Yield is the share of what you buy that ends up on the plate after trimming, peeling, boning and cooking. If a 10-pound case of broccoli gives you 6.5 pounds of usable florets, the yield is 65 percent, and the real cost of each usable pound is the purchase cost divided by 0.65.
What is a Q factor?
Q factor is a small percentage added to plate cost to cover items that are too small or too variable to cost one by one, such as cooking oil, salt, garnish, butter on the pass or condiments on the table. Many kitchens use somewhere between 2 and 8 percent. Pick a number, then check it against your monthly food cost.
Should I just multiply plate cost by three to set my price?
Multiplying by three is the same as targeting a 33 percent food cost. It is a reasonable starting point, but it ignores what the market will pay, how long the dish takes to make, and how much gross profit in dollars each plate brings in. Use the calculator for the cost side and your judgment for the rest.
How often should I re-cost my menu?
Re-cost any plate whose main ingredient moves more than a few percent in price, and walk through the whole menu at least twice a year. Volatile items like beef, seafood, eggs and produce deserve a monthly look.