The age distribution, , in Gränichen is; 580 children or 9.0% of the population are between 0 and 9 years old and 804 teenagers or 12.5% are between 10 and 19. Of the adult population, 691 people or 10.7% of the population are between 20 and 29 years old. 774 people or 12.0% are between 30 and 39, 1,174 people or 18.2% are between 40 and 49, and 956 people or 14.8% are between 50 and 59. The senior population distribution is 674 people or 10.5% of the population are between 60 and 69 years old, 503 people or 7.8% are between 70 and 79, there are 251 people or 3.9% who are between 80 and 89,and there are 37 people or 0.6% who are 90 and older.