Humphries was born in Minnesota to Debra and William Humphries. His father was a football player at the University of Minnesota. Humphries is half African-American from his father. He has two older sisters, Krystal and Kaela. His first success in sports came in competitive swimming, where he was the top 10-year-old in the nation in six events, first, beating young Michael Phelps in the remaining events. Kris Humphries held the US national record for the 50-meter freestyle for 10 and under boys for 18 years until it was recently broken. At age 12 he gave up swimming to pursue a career in basketball.