Method for ascertaining the load applied to a tyre casing when mounted on a wheel so as to constitute a pneumatic mounted assembly in rolling state with rotation speed W, said tyre casing having a crown in contact with the ground and in revolution about a natural rotational axis, comprising the following steps: - Fastening at least one sensor to the tyre casing at the crown of the tyre casing so as to generate at least one output signal sensitive to the acceleration, in the direction normal to the crown, applied to said sensor in the tyre casing; - Acquiring at least one first temporal signal Sig comprising at least the amplitude of the at least one output signal while rolling; the method being characterized by the following steps: - Delimiting the first signal Sig over a number N TdR of wheel turns so as to construct a wheel-turn signal Sig TdR, wherein N TdR is greater than 1; - Determining at least one reference speed W reference associated with at least one portion of the wheel-turn signal Sig TdR; - Normalizing the at least one portion of the wheel-turn signal Sig TdR by a variable which is a function F proportional to the square of the reference speed W reference, over a number of wheel turns N TdR, wherein N TdR is greater than or equal to 1; - Angularly resampling the at least one portion of the wheel-turn signal Sig TDR; - Defining at least one energy density S from the at least one angularly resampled normalized wheel-turn signal Sig TDR, by means of a threshold A or, if the angular pitch is fixed, at least one spectral variable from a spectral signal spect(Sig) of the at least one portion of the angularly resampled normalized wheel-turn signal Sig TDR; - Identifying the deformation Def% of the tyre casing as a function G of the at least one first energy density S or the at least one spectral variable; - Defining the load Z applied to the mounted assembly by means of a bijective function H comprising at least, as a variable, the deformation Def% of the tyre casing. - Fastening at least one sensor to the tyre casing at the crown of the tyre casing so as to generate at least one output signal sensitive to the acceleration, in the direction normal to the crown, applied to said sensor in the tyre casing; - Acquiring at least one first temporal signal Sig comprising at least the amplitude of the at least one output signal while rolling; - Delimiting the first signal Sig over a number N TdR of wheel turns so as to construct a wheel-turn signal Sig TdR, wherein N TdR is greater than 1; - Determining at least one reference speed W reference associated with at least one portion of the wheel-turn signal Sig TdR; - Normalizing the at least one portion of the wheel-turn signal Sig TdR by a variable which is a function F proportional to the square of the reference speed W reference, over a number of wheel turns N TdR, wherein N TdR is greater than or equal to 1; - Angularly resampling the at least one portion of the wheel-turn signal Sig TDR; - Defining at least one energy density S from the at least one angularly resampled normalized wheel-turn signal Sig TDR, by means of a threshold A or, if the angular pitch is fixed, at least one spectral variable from a spectral signal spect(Sig) of the at least one portion of the angularly resampled normalized wheel-turn signal Sig TDR; - Identifying the deformation Def% of the tyre casing as a function G of the at least one first energy density S or the at least one spectral variable; - Defining the load Z applied to the mounted assembly by means of a bijective function H comprising at least, as a variable, the deformation Def% of the tyre casing.