As stated in the Lorenz curve article, the straight line in the diagram represents perfect equality in a society, and Lorenz curves that are further away from that diagonal line represent higher levels of inequality. Therefore, larger Gini coefficients represent higher levels of inequality and smaller Gini coefficients represent lower levels of inequality (i.e. higher levels of equality).

In order to mathematically calculate the areas of regions A and B, it is generally necessary to use calculus to calculate the areas below the Lorenz curve and between the Lorenz curve and the diagonal line.