Deerfield Beach, FL has a population of 78,642 and is the 444th largest city in the United States. The population density is 5,231 per sq mi which is 1682% higher than the Florida average and 5673% higher than the national average. The median age in Deerfield Beach is 43 which is approximately 3% higher than the Florida average of 42. In Deerfield Beach, 48% of the population over 15 years of age are married, 59% speak English and 15% speak Spanish. 31% of Deerfield Beach residents were born in Florida, 36% were born out of state, 2% were born outside of the United States and 32% were foreign born.