Unit price guides
Short, practical guides that answer one shopping question each and show the math, so you can check every step in the calculator.
Unit price basics
How to Read Unit Price Labels
Unit price labels show the cost per ounce, pound, kg or 100 g. Learn where to find them, what to compare and the mistakes that make them misleading.
Ounces vs. Fluid Ounces: Why Mixing Them Gives Wrong Comparisons
An ounce is weight, a fluid ounce is volume. See why comparing oz and fl oz prices gives wrong answers, with honey examples, and how to convert properly.
Price per Ounce vs. Price per Pound: Which Should You Use?
Price per ounce and price per pound always pick the same winner, but each is easier for different foods. How to convert between them, with examples.
Metric vs. US Units: A Shopper’s Conversion Cheat Sheet
Grams vs. ounces, liters vs. fluid ounces, price per kg vs. per pound: the conversions shoppers need, in three tables, with worked examples.
How to Compare Multipacks and Single Items
Multipacks hide the total amount. Multiply it out and compare 6-packs, 12 × 330 mL boxes, yogurt 4-packs and single bottles per unit, with worked examples.
Deals, discounts and where to shop
Shrinkflation Calculator
Same price, smaller pack? Enter the old and new size and price to see how much the price per ounce or per kg really went up, in percent.
Is Buying in Bulk Always Cheaper?
Bulk is usually cheaper per unit — but not always. See when the bigger pack loses, and check any two sizes with the free unit price calculator.
Is Costco Really Cheaper? How to Check With Unit Prices
Warehouse clubs sell big packs, but bigger isn’t automatically cheaper. Compare club and supermarket prices per unit, including the membership fee.
Store Brand vs. Name Brand: How to Compare Fairly
Store brands often look cheaper, but package sizes differ. Compare store and name brands per unit, see when the name brand wins, and test quality yourself.
How to Factor Coupons, Cashback and Rewards Into Unit Price
A coupon changes the real price per unit. Learn which discounts to subtract — coupons, cashback, store-card prices — before comparing, with examples.
Buy One Get One vs. Percent Off: Which Deal Is Actually Better?
BOGO free is 50% off — but only if you need two. Compare BOGO, BOGO 50% off, 3-for-2 and percent-off deals by unit price, with worked examples.
Subscribe & Save: When Does It Beat the Store Price?
Subscription discounts look automatic, but the base price, pack size and delivery timing decide the real saving. How to compare per unit, with examples.
How to Build a Simple Grocery Price Book
A price book is a short list of the unit prices you usually pay. Set one up in 20 minutes, learn what to record, and see how it exposes fake deals.
Product by product
Cost per Use: How to Compare Razors, Pods and Tablets
Some products are priced per pack but used per shave, cup or load. Work out the real cost per use, with razor and dishwasher examples and a simple formula.
Bone-In vs. Boneless Meat: The Real Cost per Edible Pound
Bone-in meat is cheaper per pound on the label, but you can’t eat the bones. Work out the cost per edible pound, weigh it yourself and compare cuts fairly.
Coffee Cost per Cup: Whole Bean vs. Ground vs. Pods
Compare whole bean, ground and pod coffee by cost per cup. A simple formula, a cups-per-bag table and worked examples you can redo with your own prices.
Dry vs. Wet Pet Food: Comparing Cost per Serving and per Day
Price per pound can’t compare dry and wet food, or foods with different feeding amounts. Use the feeding guide to work out the cost per day instead.
Baby Formula: Comparing Powder and Ready-to-Feed per Prepared Ounce
Powder, concentrate and ready-to-feed formula are measured differently. Compare them per prepared fluid ounce using the label’s yield, with examples.