Children typically start kindergarten at around 5 years old, though the exact age can vary depending on the country, state, or school district. In the United States, most states require children to be 5 years old by a specific cutoff date, often August 31 or September 1, to start kindergarten that school year

. Some states or private schools may have different cutoff dates, such as December 31, allowing children who turn 5 later in the year to start kindergarten

. Kindergarten entrance ages generally range from about 4 to 6 years old, with some children starting as young as 4 if they are developmentally ready, while others may start later if they need more time to mature socially, emotionally, or academically

. Only some states require kindergarten attendance, and the compulsory school starting age varies, typically between 5 and 7 years old

. In summary:

• Most children start kindergarten at age 5.
• Cutoff dates for turning 5 vary by location, commonly around late August or early September.
• Some children start younger or older based on readiness and local rules.
• Kindergarten attendance is mandatory in some states but not all.

Parents often consider their child's developmental readiness, social skills, and family circumstances alongside age requirements when deciding the best time to start kindergarten