GDP’s reliability as a measure of economic performance has been increasingly undermined by rapid digitalisation of production and consumption between 2010 and 2024, particularly through the under-capture of intangible assets and cross-border digital value flows. Using secondary data from the IMF, OECD, and World Bank alongside simulated datasets, the study identifies structural biases in traditional national accounting frameworks and substantial cross-country differences in the extent of digital undercounting. A mixed-methods approach combining statistical trend analysis with qualitative interpretation quantifies the scale of this under-representation and highlights the resulting distortions in official GDP figures.