We describe an informative type of line graph, the frequency profile, which allows a single behavior, multiple behaviors, or the specific behavioral patterns of individuals to be graphed either post hoc or in real time from digital data. The informativeness of the frequency profile curves can be optimized through the adjustment of three parameters—window size (number of adjacent time intervals in each calculation), step size (time increment by which the window is advanced), and resolution (duration of the basic observational time interval). At extreme values, the parameters yield graphical representations that have long been in use—interval recording (at one extreme) and B. F. Skinner’s cumulative record (at another extreme). Intermediate values yield informative overlapping curves that resemble probability curves, revealing (a) overall behavioral tendencies at any point in time, (b) periods of competition among different behaviors, and (c) transitions from one behavior to another. Predictive models that generate probability curves can be compared both visually and statistically with frequency profile curves. A clear graphical presentation of the moment-to-moment behavior of an individual subject should have numerous applications in business, education, law enforcement, military, and other settings in which it is advantageous to monitor individual performance continuously, in clinical settings in which subtle behavioral changes in individual clients are analyzed, or in research settings in which the behavior of individual human or animal subjects is tracked or simulated. Examples of frequency profiles with both nonhumans and humans are presented, along with statistical comparisons between a frequency profile and predicted probabilities.