How common is stuttering?

According to the Center for Stuttering Therapy, more than 3 million Americans stutter. It affects four to five times as many males as females. Though people of all ages stutter, it is especially prevalent among young children between the ages of two and five who struggle to develop their language skills. Most eventually outgrow their stuttering habit as they get older, but there is a small subset of people who remain stutterers through adulthood.

Around five percent of children will stutter at some point during their development. Most of these children will grow out of, with or without therapy, after the age of 5. In childhood, boys are twice as likely as girls to stutter, but this number jumps to about three times as likely once adulthood is reached. About one percent of the adult population stutters.