Hardin, KY has a population of 600 and is the 18,436th largest city in the United States. The population density is 857 per sq mi which is 691% higher than the Kentucky average and 846% higher than the national average. The median age in Hardin is 33 which is approximately 16% lower than the Kentucky average of 39. In Hardin, 57% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 74% of Hardin residents were born in Kentucky, 26% were born out of state, 0% were born outside of the United States and 0% were foreign born.