It is the largest number of concurrent live streams in the website's history, Google UK was quoted by the BBC as saying.
More than eight million people flocked to their devices to watch the 43-year-old break the speed of sound live on Google's YouTube site yesterday.
Baumgartner broke the record for the highest freefall. He jumped from a capsule taken to 128,100ft (39km) above New Mexico in the US by a giant helium balloon.
It took nine minutes for him to reach the ground.
The adventurer plummeted at an estimated 1,343km/h, hitting Mach 1.24.
"On the step, I felt that the whole world is watching," Baumgartner said after the jump.
"I said I wish they would see what I see. It was amazing," he said.
The capsule from which the skydiver fell was equipped with cameras to provide a live internet feed to millions of people around the world.
A Google spokesperson confirmed that the number of viewers simultaneously watching the Red Bull Stratos stunt live on YouTube was the site's highest.
"We congratulate Felix Baumgartner and the entire Red Bull Stratos team for their successful mission, and for creating a live stream with the most concurrent views ever on YouTube," the company said on its blog.