Packaging is one of the first things a shopper notices about a product, often before reading the detailed information printed on the label. A container’s size, shape, color, materials, and familiar branding can create a rapid impression of how much product is inside and whether the item represents good value. Research in consumer psychology has shown that people do not always estimate package volume accurately from appearance alone.
Container shape in particular can influence judgments about quantity even when the actual volume is available on the label. This does not mean every package is designed to mislead shoppers, but it does mean visual design can influence purchasing decisions in ways consumers may not immediately recognize. Packaging therefore performs both a practical function and a communication function. Most people do not calculate the internal capacity of every box, bottle, jar, or pouch they encounter in a store.
Instead, consumers frequently rely
