Rockford, MI has a population of 6,044 and is the 5,738th largest city in the United States. The population density is 1,872 per sq mi which is 1756% higher than the Michigan average and 1966% higher than the national average. The median age in Rockford is 34 which is approximately 14% lower than the Michigan average of 40. In Rockford, 62% of the population over 15 years of age are married, 92% speak English and 5% speak Spanish. 73% of Rockford residents were born in Michigan, 21% were born out of state, 1% were born outside of the United States and 5% were foreign born.