The estimation of exponential decay lifetimes is important in many areas of physics, but often difficult if the waveform produced by some particular process (say, fluorescence decay) is noisy. We have used a simulation technique which makes it possible to model accurately two common waveform analysis methods. Results from actual experiments can be compared with those produced by the simulation in order to investigate the nature of the measurement system’s precision limits and thereby effect a reduction of the measurement error. Specifically, an algorithm calculating decay lifetime from two data points exhibited a one‐sigma error of 4% when the measurement signal‐to‐noise ratio was 40:1, compared with a 0.1% error of a least‐squared error algorithm under similar conditions.