Spencer, IN has a population of 2,281 and is the 10,300th largest city in the United States. The population density is 1,439 per sq mi which is 702% higher than the Indiana average and 1489% higher than the national average. The median age in Spencer is 43 which is approximately 16% higher than the Indiana average of 37. In Spencer, 53% of the population over 15 years of age are married, 96% speak English and 0% speak Spanish. 79% of Spencer residents were born in Indiana, 17% were born out of state, 1% were born outside of the United States and 3% were foreign born.