This paper examines the trends in the use of the Dice (Czekanowski-Sørensen) similarity index in studies of algae and cyanoprokaryotes. A concise overview of the characteristics of this metric is provided, considering its positive aspects and limitations. The relevance of the work is justified by the researchers' need for automation of Dice index calculations and the construction of resulting matrices. The article proposes a method for automating calculations using macros in the Excel environment. The authors provide an overview of the possibilities of this approach and offer their own macro for fast and convenient calculation of the Dice index without the need for third-party programs or formulas.