Youngstown is a city in the U.S. state of Ohio. It lies along the Mahoning River in Northeast Ohio, predominantly within Mahoning County, of which it is the county seat. The population was 60,068 at the 2020 census (estimated at 58,832 in 2025), making Youngstown the eleventh-most populous city in Ohio. Its metropolitan area, known as the Mahoning Valley, had an estimated 426,086 residents in 2024.