Manly, IA has a population of 1,551 and is the 12,484th largest city in the United States. The population density is 1,058 per sq mi which is 1837% higher than the Iowa average and 1068% higher than the national average. The median age in Manly is 38 which is approximately 1% higher than the Iowa average of 38. In Manly, 53% of the population over 15 years of age are married, 98% speak English and 2% speak Spanish. 73% of Manly residents were born in Iowa, 26% were born out of state, 0% were born outside of the United States and 1% were foreign born.