A method for correcting a fuel quantity injected by a fuel injection device during operation of an internal combustion engine, including: determining an air heat characteristic variable, on which an air heat stream fed to a combustion chamber of the engine functionally depends; determining an exhaust heat characteristic variable, on which an exhaust heat stream discharged from the combustion chamber functionally depends; determining a heat distribution factor, which specifies a fraction of the exhaust heat stream reduced by the air heat stream in relation to a heat stream fed with the injected fuel to the combustion chamber; calculating a fuel mass fed to the engine from the air heat characteristic variable, the exhaust heat characteristic variable and the heat distribution factor; calculating a comparison variable by comparing the calculated fuel mass with a fuel mass setpoint value and adapting actuation of the fuel injection device depending on the comparison variable.