The degree of digitalization and potential of growth in this sector are the new criteria that split the countries into various groups. The aim of this research is to find an easier and faster method of assessing the level of digitalization for countries, over different periods, having a sample 10 countries from Central and Eastern Europe. The research compares and groups these countries, determining the impact of four additional variables on their digitalization level. There were combined multiple analyses including comparative, cluster and panel analysis. As a result, we defined a new standardized indicator, named Digi-Index, which can be adapted for various time ranges, countries or study groups. Academic researchers or business practitioners can use the Digi-Index, the clusters and their characteristics to build development plans for the digital sector, based on each country's conditions, potential and influence factors.