The author summarizes the history of the medieval counting table, used until around 1610 by English upper classes, and remaining in use until the early 18th century by lower classes. Building her own replica and performing sample calculations mostly according to instructions in Robert Recorde’s The grounde of artes, she demonstrates that the four basic arithmetical operations could be performed easily with a practitioner’s manual tacit knowledge built through experience. A method for division is presented, demonstrating that even this challenging task could be completed by those with little formal education.