In this letter a relation is derived between hot isostatic pressing (HIP) temperature, the initial oxygen concentration of sintered Y‐Ba‐Cu‐O powder, the relative density, the oxygen pressure, and the oxygen concentration during HIP densification. The maximum attainable relative density is calculated as a function of HIP pressure. It turns out that degassing oxygen during HIP densification processing has considerable effects on densification maps. Using corrected and modified densification maps a recipe for manufacturing highly dense YBa2Cu3O7−xis presented.