We analyze 4,050 wide binary star systems involving a white dwarf (WD) and usually a main sequence (MS) star, drawn from the large sample assembled by citet[][hereafter, T20]{Tian_2020}. Using the modeling code BASE-9, we determine the systems ages, the WD progenitors ZAMS masses, the extinction values ($A_V$), and the distance moduli. Discarding the cases with poor age convergences, we obtain ages for 3,551 WDs, with a median age precision of $sigma_{tau}/tau = 20$%, and system ages typically in the range of 1-6 Gyr. We validated these ages against the very few known clusters and through cross-validation of 236 WD-WD binaries. Under the assumption that the components are co-eval in a binary system, this provides precise age constraints on the usually low-mass MS companions, mostly inaccessible by any other means.
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