The invention relates to a method for dosing of a pre-determined quantity of a solid detergent from a solid detergent reservoir (1) by dissolving some of the solid detergent in the reservoir (1) in a rinsing liquid to form a detergent solution, comprising the following steps: a) continuously or discontinuously feeding detergent solution generated at the detergent reservoir (1) into a dissolving tank (11), b) measuring the amount of rinsing liquid supplied to form the detergent solution that is fed to the dissolving tank (11), as well as any amount of rinsing liquid directly supplied to the dissolving tank (11), c) measuring the detergent concentration of the detergent solution in the dissolving tank (11), d) calculating the quantity of detergent in the detergent solution in the dissolving tank (11) by multiplication of the results of the measurements in steps b) and c), e) feeding the amount of detergent solution representing the required quantity of detergent from the dissolving tank (11) to an utilization point (13), preferably to equipment or system to be cleaned and/or disinfected. Further, the invention relates to a corresponding detergent dispenser and a preferred use of both.
