A study was carried out in which age and gender differences were studied in the performance of an empty interval production task. The duration of these intervals was 10 s, 1 and 5 min. The sample was made up of 140 subjects, half male and half female, in seven different age groups from 8 to 70 years old. The age range permitted us to identify when differences begin to be significant. The results show an age-related increase in the underproduction of the intervals. The differences between age groups attained significance from 51 to 60 years onward. With regard to gender, the main result was a greater underproduction of longer intervals (1 and 5 min) for women. These findings were interpreted in terms of different models of time estimation. (C) 2002 Elsevier Science B.V. All rights reserved.