Calculating how much the food you sell costs you to sell is a very important practice in running a profitable restaurant. Knowledge is power, and knowing your food cost compared to your sales and your ideal food cost is very empowering information. By figuring your food cost percentage, you have an early warning system to alert you to potential theft and waste.

Before we get into the process for calculating food cost, it’s good to talk about how often this should be done. I suggest calculating your food costs at the end of every week. If you happen to have a cost control issue, it’s best to know as close to the time the occurrence happened as possible. The farther you get away from an occurrence that caused a cost problem, the harder it is to determine what that occurrence was.

You are going to need to track a few pieces of information to calculate your food costs. You will need to know:

• How much is my starting inventory for the period I am evaluating?
• How much is my ending inventory for the period I am evaluating?
• How much food did I purchase during that period?

This is all the information necessary to calculate actual food costs for any given period. How long that period is depends on you. As I said, I suggest evaluating food costs every week.

In addition to knowing your actual food costs, you’ll need a couple other pieces of information to compare the actual food cost to:

• What is your ideal food cost for the period being evaluated? (we’ll discuss how to calculate ideal food cost also)
• What are your total sales for the period being evaluated? (you’ll also need to track your sales by item to calculate your ideal food cost)

Now let’s go one step at a time to get these powerful pieces of information.

Calculating your actual food cost starts by taking an inventory of all your food items at the same time every week. Choose one time as the starting and ending time for all your reporting for that week. I suggest ending your reporting after the end of business on Sunday, but before the beginning of business on Monday. Inventory levels are usually at their lowest on Sunday, so inventory takes less time to count and calculate.

The inventory that you take every week will serve as the starting inventory for the week to follow, but also the ending inventory for the week that is concluding. It will be used in both capacities to calculate food costs depending on whether the calculations are for the past week or the coming week. By counting your inventory, and using a spreadsheet to multiply out the value of all your items on hand, you will come up with a dollar amount that shows you how many dollars in inventory you have on hand.

This starting inventory is the beginning to the food cost equation. The equation looks like this:

By taking a physical count of all your food on hand, you’ll have the starting inventory and the ending inventory parts to this equation. From there, you simply have to track your purchases within that time period. For this number, you’ll use dollar amounts from invoices received in the period being evaluated. It does not matter to the equation when that food is actually paid for.

Start with an inventory you took on the Sunday before a week started. Add all the dollar amounts for food received during that week. Subtract the amount of your inventory counted on the following Sunday. The resulting number is the cost of goods sold, or food cost, for the week.

Ideal food costs are the amount of money the food you sold during a given period should have cost you. Compare your ideal food cost to your actual food cost to help you identify when there is a breakdown in your system. If your actual food cost goes up for a period, your ideal food cost should go up too. If it doesn’t, then you’ve just identified a problem, possibly theft or waste. If your ideal food cost does rise with your actual food cost, then you know your food cost is high not because your staff did something wrong, but because of the sales mix of your menu items for the period. This is important to know, because most high food cost menu items also contribute more gross profit dollars to your bottom line, so a high food cost for that period is not be a bad thing. The only way to know whether it is bad or good, is to compare it to your ideal food cost.

Here are the equations to figure your ideal food cost:

In a perfect world, your ideal food cost should match your actual food cost exactly. Since it’s impossible to perfectly measure every piece of food, or track every piece of waste, you will see some variance between your actual and ideal food costs. You have to decide how large a variance is acceptable. I believe you should expect to keep your actual and ideal costs within .5% of each other. Variances larger than this tend to point to problems in your system. These problems could include theft, waste, under-portioning, over-portioning, poor prep procedures, bad food receiving procedures, or other problems.

What we haven’t covered yet is the “percentage” part of food costs. I’m sure you’ve noticed that other restaurateurs express their food costs in a percentage. I also suggested your ideal and actual food costs stay within .5% of each other.

A food cost percentage is an expression of what your food cost you to serve compared to the sales you made during the period you’re evaluating.

The simple formula for figuring this percentage is:

The resulting percentage is the percent of your sales that go to pay for the food you sold, whether it’s actual or ideal. These percentages make it easy for you to compare your actual and ideal costs to each other, but also make it easy to compare food costs from different weeks, months, quarters or years to each other.

I hope this explanation helped you learn how to calculate your food costs. Calculate them every week, along with your ideal costs, and you’ll find that the extra attention you are paying to your costs will open your eyes to many opportunities to save money in your restaurant or food service.