The 44-year-old says that nobody could have imagined Saturday's 5-2 victory over Bayern Munich going any better
The Signal Iduna Park side stormed to victory with goals from Shinji Kagawa and Mats Hummels complementing a Robert Lewandowski hat-trick.
The cup victory completed a domestic double for Dortmund, and speaking after the game Klopp said that he was lost for words at his side's achievements.
"It was a Pokal final that no-one in Dortmund could have imagined going any better. We were cool, scored great goals ... what's going on inside us definitely cannot be put into words," he said according to Kicker.
It was a message echoed by captain Sebastian Kehl, who felt that his side were worthy victors in the Berlin showpiece.
"We've shown that we rightly won the championship and the cup. We were always there. It was an indescribable feeling we had today. Five goals against Bayern - sensational!" He concluded.
Saturday's victory ended a 23-year-run without the DFB Pokal for Borussia Dortmund.