The purpose of the study was to comprehensively analyse the impact of cryptocurrencies on the global economy and financial systems. Cryptocurrencies are considered as blockchain-based digital assets with transparent and secure transactions, and they are compared with fiat money in terms of functions, liquidity, speed of operations, and stability. It has been revealed that cryptocurrencies provide fast cross-border settlements and access to new financing channels, but are accompanied by increased volatility, while fiat money retains stability and government control over the money supply. The research methods included descriptive and dynamic analysis of the capitalisation of stablecoins, comparative analysis of cryptocurrencies and fiat money by emission characteristics, regulation, volatility, and international use, case analysis of individual countries (USA, China, Japan, Germany, Switzerland, Kazakhstan), and graphical visualisation of data. The results showed that cryptocurrencies provide fast cross-border settlements and expand the capabilities of financial technologies, while fiat money maintains stability and government control over the money supply. An analysis of the capitalisation of stablecoins and on-chain Assets Under Management for 2023-2025 testified to the institutionalisation of the market: in 2024, the capitalisation of stablecoins exceeded USD 200 billion, and in 2025 reached USD 250-300 billion with assets under management, which indicates the establishment of sustainable on-chain models and the integration of digital assets into the financial system. The results of the study confirmed the impact of digital assets on capital allocation, investment flows and financial stability, and also allow predicting the further development of global payment and investment networks. The practical significance of the study lies in the possibility of using the findings to develop strategies for regulating and introducing cryptocurrencies into national financial systems
blockchain; capitalisation; investments; financial technologies; transactions