In the context of Energy Internet, the power grid exhibits the characteristics of “double high” and “double random”, causing frequent, unpredictable voltage and frequency fluctuations and hence new power quality issues. It has?attracted some attention on how to realize the accurate measurement of electric energy under dynamic conditions in order to ensure the fairness and justice of the energy trade. The paper reviews the existing electric energy metering algorithms from both steady-state and dynamic aspects and summaries their principles, technical characteristics, including mechanisms of how the steady-state algorithms, such as dot product sum and fast Fourier transform, become unfit to dynamic measurement signals. The principle, technical characteristics, and limitations of dynamic algorithms for estimating fundamental frequency, as well as time-frequency analytical dynamic algorithms including short-time Fourier transform, wavelet transform, Hilbert-Huang transform, and S-transform, are compared. Specifically, the advantages and disadvantages of the wavelet transform method and its application prospects are focused on. Finally, the future research trends of dynamic energy metering algorithms are discussed.