Food cost percentage is the single most useful number in the kitchen: it tells you what share of every food dollar you spend to make what you sell. It's easy to calculate once you know the formula — the hard part is keeping it current. This guide gives you the formula, a fully worked example, the difference between plate cost and period cost, and the target ranges to aim for.
You can absolutely do this by hand each period. But if you'd rather not, Lowboy keeps the number current on its own — so your time goes back to the kitchen, not the calculator.
At its core, food cost percentage is one division:
COGS is your cost of goods sold — the actual dollar value of the food you used to generate your sales in a period. You don't just add up invoices, because you start and end the period with product on the shelf. So COGS itself has a formula:
Beginning inventory is the value of everything in your walk-in, dry storage and freezers at the start of the period. Purchases is everything you bought during it. Ending inventory is what's left at the end (which becomes next period's beginning inventory). The result is what you truly consumed.
Say you're closing out a month. You count your inventory at the start and end, and total your invoices for purchases:
Now pull your food sales for the exact same date range from your POS. Say food sales were $60,000. Divide and multiply by 100:
So this kitchen spent about 31.7 cents on food for every dollar of food sales. That's within a typical full-service range — but whether it's good depends on the target for this concept, and on the trend from month to month.
There are two food cost numbers, and you want both:
What a dish should cost. Take the recipe's total ingredient cost and divide by the menu price. A $3.00 plate on a $12 menu item is a 25% plate cost. This is your theoretical best case if nothing is wasted.
What actually happened across all sales — the COGS ÷ sales calculation above. It captures reality: waste, over-portioning, spoilage, comps, theft and price creep all live in this number.
The gap between them is where your money goes. If your plate costs say you should be running 27% but your actual period cost is 33%, that six-point gap is six points of your sales leaking somewhere between the recipe card and the register. Closing it is the real work — see how to lower food cost and how to reduce food waste.
There's no universal "right" number — it varies by concept, menu mix and market. As a general industry rule of thumb, these ranges are where many operators land (treat them as orientation, not a rule to obey):
The number that matters most is your own trend. A steakhouse running 38% can be perfectly healthy; a sandwich shop running 38% is probably bleeding. Set a target for your concept, then watch whether you're holding it, drifting up, or improving.
Every free calculator online makes you type in figures you had to gather by hand. Lowboy is the sous-chef that gathers them from the paper you already handle. Snap your invoices and menu, connect your sales, and it computes plate cost and period cost continuously — computed from your numbers, never guessed — so your food cost percentage is always current, not a month-old estimate.
It's POS-agnostic — Square today, Clover and Toast coming, or just snap a menu and a sales figure. One flat $149/mo (or $1,490/yr — two months free), whole crew included, 30-day money-back. Want the number without typing anything? Try the free food cost % calculator, or run the audit on your actual paper.
Do the math: a kitchen spending about $50,000 a month on food that trims that by just 1% saves roughly $500 a month — about 3.4× the $149 plan. One caught price hike or one re-priced dish usually clears it.
Add the hours back, too — no spreadsheet nights, no manual invoice entry, no rebuilding the prep list when the menu changes.
Less time on the back office, more time on the food, your crew, and the reason you opened.
Get your free audit →