Abstract: A digital rate monitor including a microprocessor operating under program control to receive and process event pulses to calculate the rate of the event pulses, and display the calculated rate. The rate is calculated by accumulating a batch of pulses and measuring the time it takes to accumulate such number of pulses. The batch size for a given calculation is a function of the event pulse rate, and a different batch size is automatically selected if the event pulse rate increases or decreases within a certain range. The rate is calculated once per second by averaging sixteen pulses for high speed inputs, four pulses for intermediate rates, and using a single pulse for low speed inputs.