Melba, ID has a population of 542 and is the 19,071st largest city in the United States. The population density is 1,357 per sq mi which is 7014% higher than the Idaho average and 1398% higher than the national average. The median age in Melba is 36 which is approximately 1% higher than the Idaho average of 36. In Melba, 60% of the population over 15 years of age are married, 86% speak English and 13% speak Spanish. 49% of Melba residents were born in Idaho, 44% were born out of state, 1% were born outside of the United States and 6% were foreign born.