An unbeaten 10-match run, the eighth win of which was secured with a 2-0 victory over Crystal Palace thanks to a double from Sadio Mane, not only secured Champions League football but lifted the Reds above Chelsea.
Klopp's side were seven points adrift of the top four prior to their run starting but 26 points from a possible 30 have ensured they will play in Europe's elite club competition again.
"It's big, come on. If someone told me five, six, eight weeks ago we can finish the season in third… it was out of reach, barely possible," said Klopp.
"Even when good things happened this season it didn't feel too good. Injuries followed us all season.
"Fighting through this and finishing here in third is the best lesson you could learn in life. From nowhere to the Champions League in five weeks is a massive achievement.
"It is great. It is outstanding. From outside you cannot really understand - because we are Liverpool, we have to perform, we have to fight through. We were constantly sorting problems.
"It was so nice we could use the last five, six weeks to give this season a proper turnaround and I am so happy for the Champions League that they don't have to play without us.
"Outstanding achievement from the boys. Man City rightly won the league this season; congratulations again but because we cannot be champions, it doesn't mean we can't have targets and the target was international (European) football."