The average mile time, or 50th percentile for girls depends on the age of the female, but varies between 10 and 11 minutes. For a 12-year-old girl, the average mile time is 11 minutes and 5 seconds. Between the ages of 10 and 14, the average girls' mile time improves from 11 minutes and 22 seconds to 10 minutes and 6 seconds.
Male runners of the same age complete a mile run more quickly than girls, on average.
Girls running a half mile can complete the run at a time of between 55 minutes and 5 minutes, 54 seconds. These times are based upon an age range of 6 to 10 years old, with 10-year-olds averaging 5 minutes.