Kapolei, HI has a population of 19,206 and is the 2,264th largest city in the United States. The population density is 4,641 per sq mi which is 3544% higher than the Hawaii average and 5023% higher than the national average. The median age in Kapolei is 33 which is approximately 16% lower than the Hawaii average of 39. In Kapolei, 56% of the population over 15 years of age are married, 75% speak English and 1% speak Spanish. 66% of Kapolei residents were born in Hawaii, 16% were born out of state, 5% were born outside of the United States and 14% were foreign born.