Johnstonville, CA has a population of 1,183 and is the 14,119th largest city in the United States. The population density is 142 per sq mi which is 39% lower than the California average and 56% higher than the national average. The median age in Johnstonville is 37 which is approximately 4% higher than the California average of 36. In Johnstonville, 65% of the population over 15 years of age are married, 98% speak English and 2% speak Spanish. 79% of Johnstonville residents were born in California, 19% were born out of state, 0% were born outside of the United States and 1% were foreign born.