Background Most of human interactions moved to the cyberspace for much of the pandemic. It was no surprise that online violence was also on the rise. One of the objectives of this study was to describe the prevalence and risk factors of online gender-based violence (OGBV) perpetration during the COVID-19 pandemic. Results The final analysis included 1006 respondents, 84.2% of whom were women and 94.5% were heterosexual. Over 60% of respondents admitted having perpetrated at least one type of OGBV once. It included 58.6% of women who admitted having perpetrated OGBV. Logistic regression analysis identified anxiety, online disinhibition, and history of victimization as independent risk factors of perpetration with an adjusted odds ratio (aOR) of 1.82 (95% CI 1.30–2.56), 1.38 (95% CI 1.03–1.85), and 9.72 (95% CI 5.11–18.51), respectively. Sub-group analysis that identified these factors also facilitated increased frequency and severity of OGBV perpetration. Conclusions We found a high proportion of OGBV perpetration among young adults during the pandemic among all genders although women were grossly overrepresented among the respondents. Risk factors of perpetration included anxiety, online disinhibition, and prior victimization. The pandemic situation which heightened general anxiety and increased dependency on online communication may facilitate the perpetration of OGBV. The generalization of this result should pay attention to the caveat that the demographic of respondents is heavily skewed toward women.