Glycosidases are essential enzymes that cleave glycoside bonds. The presence of glycosidases have been widely used to detect pathogens, label cells/tissues, and report specific diseases. We have developed a rapid electrochemical assay to detect glycosidases. Exposure of electrochemically inactive substrates to glycosidases releases glucose, which can be measured easily using an electrochemical cell. Five different glycosidases were detected rapidly within 1 h using disposable electrodes. This assay could readily be incorporated into repurposed glucose meters to rapidly detect glycosidases, which in turn could be useful to report the presence of a pathogen or illness.