A system for recalculating a formula previously used in preparing a mixture made from adding at least two components. The system includes a control system and salon management software. The control system has a processor, a computer-readable memory, and a display. The memory contains software configured to receive a formula defining instructions for blending a hair dye mixture using one or more blending materials and amounts recommended for the hair dye mixture. The salon management software is stored in the computer-readable memory and executed by the control system. The salon management software is in communication with the control system to exchange information on customers and formulas of hair dye mixtures associated with the customers.