And its creator, 40-year-old Gregg Nigl of Ohio, did not even realize he had a perfect bracket.
"It's really unbelievable." It's kind of a fluke, "Nigl said.
Nigl, a neuropsychologist, has accurately predicted the outcome of all 48 games so far this year's online bracket challenge.
The NCAA started tracking online brackets from its own site, ESPN, CBS, Yahoo, Fox, and Sports Illustrated.
Nigl has Gonzaga winning the tournament over Kentucky.
What his secret?
"You can not watch every college game so you've got to go to some bracketology and go with the teams that you like," Nigl said.
We want to see if his winning streak continues with Thursday's games.