The age distribution, , in Dietwil is; 129 children or 11.3% of the population are between 0 and 9 years old and 153 teenagers or 13.4% are between 10 and 19. Of the adult population, 153 people or 13.4% of the population are between 20 and 29 years old. 189 people or 16.5% are between 30 and 39, 220 people or 19.2% are between 40 and 49, and 140 people or 12.2% are between 50 and 59. The senior population distribution is 79 people or 6.9% of the population are between 60 and 69 years old, 54 people or 4.7% are between 70 and 79, there are 24 people or 2.1% who are between 80 and 89,and there are 4 people or 0.3% who are 90 and older.