This paper discusses the large signal performance of transistor circuits with feedback. An algorithm is proposed for representing the transfer characteristics of such transistor circuits using Fourier-series approximations. Using the Fourier-series approximations, closed-form expressions are obtained for the harmonic and intermodulation performance of transistor circuits with feedback. Using these expressions the most widely used distortion components, for example the third-order intercept point, the second-order intercept point, the cross modulation and the intermodulation free dynamic range, can be predicted. The special case of the sufficiently small input amplitudes is considered and the results are compared with previously published results, SPICE simulations, which confirm the validity of the proposed algorithm, are included.