Medford Lakes, NJ has a population of 4,081 and is the 7,359th largest city in the United States. The population density is 3,581 per sq mi which is 358026% higher than the New Jersey average and 3853% higher than the national average. The median age in Medford Lakes is 45 which is approximately 15% higher than the New Jersey average of 40. In Medford Lakes, 69% of the population over 15 years of age are married, 97% speak English and 1% speak Spanish. 53% of Medford Lakes residents were born in New Jersey, 43% were born out of state, 2% were born outside of the United States and 2% were foreign born.