February 2022 marks the 100th issue of the Teaching English as a Second Language Electronic Journal (TESL-EJ), set up in 1994 as the brainchild of a group of scholars who saw the need for a freely distributed electronic academic journal covering a diverse array of interests within teaching English as a second language long before the term “open access” was coined. The present study constitutes a bibliometric analysis of the first 99 issues of TESL-EJ. Through cross-sectional and historical analysis of a range of key metrics, notably the scale of its output and citations by other authors, frequency of topics explored, most productive and influential author affiliations and countries, and the extent of author collaboration, the study analyzes the growth and development of research activity as reflected in the publication’s output during the period under study. The study found that the nature of the journal’s output has evolved over the years from anecdotal practitioner reviews and thought pieces to rigorous empirical research. As a US-based journal, North American scholarship is well-represented across TESL-EJ’s output, particularly in studies contextualized in tertiary-level settings. There has been a consistent tendency towards non-specialist research topics within teaching English to speakers of other languages (TESOL), notably, EFL, writing, language learning, English teacher, English language learner, reflective of the journal’s large, global readership. The implications for the journal’s stakeholders, the editorial team and scholars considering submission, are discussed.