Kellogg, ID has a population of 2,279 and is the 10,306th largest city in the United States. The population density is 573 per sq mi which is 2906% higher than the Idaho average and 533% higher than the national average. The median age in Kellogg is 36 which is approximately 1% higher than the Idaho average of 36. In Kellogg, 51% of the population over 15 years of age are married, 98% speak English and 2% speak Spanish. 47% of Kellogg residents were born in Idaho, 52% were born out of state, 0% were born outside of the United States and 1% were foreign born.