在经济学中，弹性用于计量一个变量的改变将在多大程度上影响其他变量。这一概念是由阿尔弗莱德·马歇尔提出的。弹性用因变量的变化率与自变量的变化率之比表示。弹性的概念可以应用在所有具有因果关系的变量之间。作为原因的变量通常称作自变量，受其作用发生改变的量称作因变量。例如自变量和从变量之间存在关系，则的弹性：

常见的经济学弹性有：

In economics, elasticity is the measurement of how responsive an economic variable is to a change in another. It gives answers to questions such as:

An elastic variable (with elasticity value greater than 1) is one which responds more than proportionally to changes in other variables. In contrast, an inelastic variable (with elasticity value less than 1) is one which changes less than proportionally in response to changes in other variables. A variable can have different values of its elasticity at different starting points: for example, the quantity of a good supplied by producers might be elastic at low prices but inelastic at higher prices, so that a rise from an initially low price might bring on a more-than-proportionate increase in quantity supplied while a rise from an initially high price might bring on a less-than-proportionate rise in quantity supplied.