Consumer surplus measures the benefit to buyers of participating in a market. It is measured as the amount a buyer is willing to pay for a good minus the amount a buyer actually pays for it. For an individual purchase, consumer surplus is the difference between the willingness to pay, as shown on the demand curve, and the market price. For the market, total consumer surplus is the area under the demand curve and above the price, from the origin to the quantity purchased. The demand curve helps use measure this relationship by looking at the area below the demand curve and above the price is the sum of the consumer surplus. The demand curve shows the maximum amount buyers are willing to pay for a given market quantity, the price given by the
