The analysis of reactor power fluctuations has proved useful for many reactors. Limited analysis techniques giving specific noise characteristics are proposed. Utilizing the Gaussian property of reactor noise, simplified methods of obtaining the standard deviation are given. The concepts of the easily evaluated correlation times and moments of the power spectral density are applied in the noise analysis of several boiling reactors. It is shown that standard deviations of filtered reactor noise can give spectral shape information. Finally simplified analysis of narrow band spectra is discussed with regard to obtaining the resonance width.