We developed three analytical methods for the determination of carbohydrazide at different concentration levels. One involves the volumetric titration of the analyte with bromate ion and dead-stop end-point detection, and is applicable to concentrations above 10 mg/l., so it can be used for standardizing carbohydrazide solutions. A second, spectrophotometric method is based on the reduction of FE(III) and measurement of the absorbance of the Fe(II)-ferrozine complex, and features an applicability range of 25-700,μg/l. carbohydrazide. The third method uses differential pulse polarography and the oxidation of carbohydrazide in a basic medium at a dropping mercury electrode to determine the analyte. This last method is the most sensitive of the three and also that offering the widest determination range: from 4 to 3000 μg/l. carbohydrazide. © 1992.