For this study, we searched academic journal databases and journal lists from China, Japan, and Korea, dating up to July 2018, to determine the percentage of domestic journals published in English in these three East Asian countries. This study differs from most previous studies that relied on article indexes and abstracts for determining the language of academic journals. We took advantage of the full-text searching capabilities that online journal archives allow. We found that journals labelled ‘English-Japanese mixed’ or ‘Korean and English’ typically have only English metadata and not English articles and that the vast majority of domestic journals in China, Japan, and Korea are still published in the national language with no English full text. Due to China’s fast development and its low percentage of English journals, the world may experience, for the first time in nearly a century, a decrease in the worldwide percentage of active academic journals published in the English language.