DeWitt, IA has a population of 5,264 and is the 6,231st largest city in the United States. The population density is 879 per sq mi which is 1509% higher than the Iowa average and 870% higher than the national average. The median age in DeWitt is 39 which is approximately 1% higher than the Iowa average of 38. In DeWitt, 56% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 70% of DeWitt residents were born in Iowa, 27% were born out of state, 1% were born outside of the United States and 2% were foreign born.