Dayton, OH has a population of 141,143 and is the 188th largest city in the United States. The population density is 2,532 per sq mi which is 883% higher than the Ohio average and 2695% higher than the national average. The median age in Dayton is 33 which is approximately 15% lower than the Ohio average of 39. In Dayton, 36% of the population over 15 years of age are married, 93% speak English and 3% speak Spanish. 70% of Dayton residents were born in Ohio, 24% were born out of state, 1% were born outside of the United States and 5% were foreign born.