Self-concept begins to develop in early childhood. This process continues throughout the lifespan. However, it is between early childhood and adolescence that self-concept experiences the most growth.

By age 2, children begin to differentiate themselves from others. By the ages of 3 and 4, children understand that they are separate and unique selves. At this stage, a child's self-image is largely descriptive, based mostly on physical characteristics or concrete details. Yet, children increasingly pay attention to their capabilities, and by about 6 years old, children can communicate what they want and need. They are also starting to define themselves in terms of social groups.

Between the ages of 7 and 11, children begin to make social comparisons and consider how they’re perceived by others. At this stage, children’s descriptions of themselves become more abstract. They begin to describe themselves in terms of abilities and not just concrete details, and they realize that their characteristics exist on a continuum. For example, a child at this stage will begin to see himself as more athletic than some and less athletic than others, rather than simply athletic or not athletic. At this point, the ideal self and self-image start to develop.

Adolescence is a key period for self-concept. The self-concept established during adolescence is usually the basis for the self-concept for the remainder of one’s life. During the adolescent years, people experiment with different roles, personas, and selves. For adolescents, self-concept is influenced by success in areas they value and the responses of others valued to them. Success and approval can contribute to greater self-esteem and a stronger self-concept into adulthood.