Total utility is the sum total of marginal utility from the consumption of different units of a commodity. For example, a person consumes eggs and gains 50 utils of total utility. This total utility is the sum of utilities from the successive units (30 utils from the first egg, 15 utils from the second and 5 utils from the third egg). Summing up total utility is the amount of satisfaction (utility) obtained from consuming a particular quantity of a good or service within a given time period. It is the sum of marginal utilities of each successive unit of consumption. Marginal utility means addition to total utility when one or more unit of a good is consumed.For example, when a person increases the consumption of eggs from one egg to two eggs, the total utility increases from 30 utils to 45 utils.The marginal utility here would be the 15 utils of the 2nd egg consumed. Marginal utility, thus, can also be described as difference between total utility derived from one level of consumption and total utility derived from another level of consumption. Marginal utility is the difference of total utility.