The distribution of oceanic water masses and their properties, such as ventilation constitute fundamental parameters, for instance, the thermohaline circulation patterns and biogeochemical processes in the marine systems.&nbsp; The distributions of main water masses in the Atlantic Ocean have been comprehensively documented in a companion study (Liu and Tanhua, 2021), this<span> </span>study presents quantitative assessments of water mass age characteristics and ventilation time scales through multi-tracer analysis incorporating chlorofluorocarbon-12 (CFC-12), sulfur hexafluoride (SF₆), and argon-39 (³⁹Ar). Here we use two distinct age concepts: mean-age as an integrative metric of water mass chronology, and mode-age as a proxy for advective time scales. Empirical results demonstrate systematic age progression with increasing pressure and along water mass trajectories.&nbsp; Surface layer central waters exhibit mean ages up to ~100 years and mode ages reaching ~30 years. In the intermediate layer, meridional age gradients characterize the Antarctic Intermediate Water (AAIW) reaching maximum mean-age (~300 years) and mode-age (~80 years) at 30 &deg;N, whereas zonal variations manifest in Mediterranean Water (MW) with peak values (~400 years in mean-age, ~100 years in mode-age) observed in equatorial regions. As the dominant deep water component, North Atlantic Deep Water (NADW) exhibits extreme ages in the Antarctic Circumpolar Current (ACC) region at 50&deg;S, achieving mean age ~600 years and mode age ~100 years. Bottom layer water masses display their oldest signatures:&nbsp; Antarctic Bottom Water (AABW) from the Weddell Sea reaches ~600 years (mean) and ~100 years (mode) at equatorial latitudes, while its extension, Northeast Atlantic Bottom Water (NEABW), attains exceptional values of ~800 years (mean) and ~120 years (mode) at 50&deg;N. The age analysis reveals significant basin-scale asymmetries, with eastern basins exhibiting younger ages compared to western counterparts.&nbsp; Ventilation efficiency modulates these age distributions, as evidenced by lower mode-ages and reduced apparent oxygen utilization (AOU) in better-ventilated western basins.&nbsp; The calculated oxygen utilization rate (OUR) demonstrates spatial concordance with dissolved oxygen (DO) concentrations, corroborating enhanced oxidative processes in high-oxygen regimes. This integrated age framework provides novel insights into water mass ventilation dynamics and their biogeochemical implications through quantitative characterization of temporal-spatial age distributions across multiple oceanographic provinces.</p> <p><strong>Key words: </strong>Water Mass, Atlantic Ocean, Transient Tracer, Mean- and Mode-age, Ventilation, GLODAPv2 data product