Kinkel had pleaded guilty to four counts of murder and 26 counts of attempted murder.
The now 17-year-old Kinkel opened fire in his high school cafeteria in May 1998, killing two students and injuring 25 others. The shooting came a day after the teen killed his parents and rigged their bodies with explosives.
Kinkel’s rampage came after he was expelled from school for having a stolen gun in his locker.
The teen, who read a statement in court Wednesday, said he loved his parents and will take responsibility for his actions.
“Nothing I can do can take away from the pain and destruction I caused,” he said. “I am truly sorry for all of this.”
Throughout the week-long proceedings, victims and family members gave emotional accounts of how Kinkel’s actions affected them.
Delivering Kinkel’s sentence, Judge Jack Mattison said the victim’s statements led him to believe “this case needed accountability for each of the wounded.”