The present disclosure relates to a bolus calculator for determining a bolus of insulin, the bolus calculator having an input configured to be fed with a time series (h(t-t)) of blood glucose values and to store at least one known pulse response (x(T)) representing an active profile of at least one insulin, wherein the bolus calculator is configured to convolute the time series (h(t-T)) of blood glucose values with the known pulse response (x(T)) to obtain the bolus and to a method for calculating a bolus of insulin, comprising feeding a time series (h(t-T)) of blood glucose values into an input of a bolus calculator and storing at least one known pulse response (x(T)) representing an active profile of at least one insulin in the bolus calculator, convoluting the time series (h(t-T)) of blood glucose values with the known pulse response (x(T)) to obtain the bolus.
