McKinleyville, CA has a population of 16,948 and is the 2,531st largest city in the United States. The population density is 814 per sq mi which is 250% higher than the California average and 798% higher than the national average. The median age in McKinleyville is 37 which is approximately 2% higher than the California average of 36. In McKinleyville, 52% of the population over 15 years of age are married, 92% speak English and 5% speak Spanish. 68% of McKinleyville residents were born in California, 27% were born out of state, 1% were born outside of the United States and 4% were foreign born.