Aging is a complex biological process characterized by progressive functional decline and increased risk of chronic diseases. In recent years, DNA methylation-based epigenetic clocks have emerged as some of the most robust biomarkers for estimating biological age.

This review critically evaluates the current landscape research-based epigenetic clocks, and their transition into direct-toconsumer testing. Their key strengths are discussed as well as their limitations, and translational potential, with particular emphasis on the growing demand for simplified, cost-effective, and analytically accessible epigenetic clocks, which should maintain predictive accuracy while enabling broader implementation in clinical and epidemiological settings.