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The time interval represented by the Djadokhta Formation is difficult to estimate. Based on patterns of mammalian biostratigraphy, exposures of the Djadokhta Formation throughout the region have been suggested to be Campanian in age (Kielan-Jaworowska, 1974; ~80 Ma, Jerzykiewicz and Russell, 1991; Jerzykiewicz et al., 1993). However, because the lower and upper boundaries of the Djadokhta Formation cannot be observed in outcrops at the type and other localities, it is unknown if a Campanian age applies to the entire formation throughout the region. The thick eolian redbeds that dominate these localities do not lend themselves easily to age assessments using paleomagnetostratigraphic means (J. Hicks, pers. comm.); however, recent paleomagnetostratigraphic work by Dashzeveg et al. (2005) suggests that the Byan Dzak sediments were deposited during the rapid succession of polarity changes during the Late Campanian (~71–75 Ma).

Djadokhta-like outcrops are also present at Khulsan, Nemegt, and Khermeen Tsav in the Nemegt Basin. The upper boundary with the Nemegt Formation can be observed at Nemegt. At Khermeen Tsav, the upper and lower boundaries with fluvial beds are observed. The upper boundary of the formation is transitional with the overlying Nemegt Formation, where Djadokhta-like redbeds are referred to as the Baruungoyot Formation (Eberth et al., 2009).