Toting up, which means adding up a series of numbers, can have several antonyms depending on the context. If you are subtracting numbers or deducting an amount, the antonyms would be subtracting, deducting, or taking away. If you are dividing numbers, then the antonyms would be multiplying or adding. Similarly, if you are measuring the weight of an object, the antonyms would be lightening or reducing the weight. In more general terms, the antonyms of toting up could be simplifying, shortening, or minimizing. Ultimately, it is important to consider the context when identifying antonyms for a word, as the opposite can vary based on the specific usage.