In a method for estimating the remaining life span of an X-ray radiator that has been installed in an X-ray apparatus and is operational, under specified test conditions and at time intervals, a measurement value that is indicative for the remaining life span of the X-ray radiator is determined and stored in a. A forecasted progression of future measurement values is then forecasted from the instantaneous measurement value and previous measurement values that were determined under identical test conditions, which also are stored in the memory. The forecasted remaining life span of the X-ray radiator is then determined based on the forecasted progression and a limit value that is associated with the individual X-ray radiator, which is stored in the memory. Alternatively or additionally, a characteristic curve that is associated with the measurement value and with the individual X-ray radiator is stored in the memory. In that case, the forecasted remaining life span of the Xray radiator is forecasted based on the instantaneous measurement value, the characteristic curve, and the limit value.