In a method for determining a control parameter for a fuel injector of an internal combustion engine, the problem of enabling more precise determination of the control parameter, even if the fuel pressure (FUP) present on the fuel injector varies, is solved in that the fuel pressure (FUP) present on the fuel injector during the injection (I1, I2, I1′, I1″) is concluded while allowing for the time of the fuel pressure value detection and/or the crankshaft angle position of the internal combustion engine during the detection of the fuel pressure value, and that the control parameter is determined based on the fuel pressure (FUP) that was concluded.