Middletown, IN has a population of 2,624 and is the 9,548th largest city in the United States. The population density is 2,296 per sq mi which is 1179% higher than the Indiana average and 2434% higher than the national average. The median age in Middletown is 36 which is approximately 5% lower than the Indiana average of 37. In Middletown, 48% of the population over 15 years of age are married, 98% speak English and 0% speak Spanish. 82% of Middletown residents were born in Indiana, 17% were born out of state, 0% were born outside of the United States and 0% were foreign born.