That number, of course, included those who could have been working at their desks. Many more millions tuned into the television broadcast.
And in Philadelphia, many went to bars to watch the game with fellow soccer fans, which required some flexible scheduling and fast talking.
At Brauhaus Schmitz, a German bar on South Street, the crowd chose country. Germany and U.S. fans sat by side, yelling for their teams and downing steins of pilsners.
Lindi von Mutius, executive director of the German Chamber of Commerce Inc., was there with 40 colleagues who work locally for German companies.
"My job is to work on German American trade relations, so what's better than to watch the Germany-America game? It's just research," von Mutius said with a laugh.
Some fans said they put in for vacation days when they learned the game would be played Thursday. Others had to conjure up creative excuses for the midweek holiday or rely on the kindness of bosses.
One man sitting by the bar said he worked for the Navy. He already had taken Friday off for a wedding and had a rehearsal dinner to go to after the game.
He told his boss he'd need all of Thursday to attend to wedding duties.
"I just happen to be here drinking," said the man, grinning. Naturally, he thought better of giving his name.
A man who works in a suburban bank also asked for anonymity. For good reason: He had informed his boss that he wouldn't be able to make it to a 10 a.m. staff meeting. He gave no explanation.
His boss asked no questions and moved the meeting up to 9. So the man went to his meeting, then, at its conclusion, headed to Brauhaus Schmitz.
A crowd of fans in U.S. soccer jerseys spilled out of Fadó Irish Pub and onto the corner of 15th and Locust during the game.
One man who works for the Deloitte consulting firm stood in a corner of the bar, celebrating the beginning of his 21/2-week vacation. He had planned to spend it watching the rest of the World Cup.
There was little room to move in Fadó, which brimmed with U.S. supporters. Dozens more outside watched on two flat-screen televisions.
A young man standing by the bar said he'd normally be working at that hour at Systems Solution Inc. in King of Prussia. But his car radiator broke that morning, and he couldn't make it to work. Seriously, he insisted.
With his car in the shop, and getting to work not an option, he figured he'd make the best of it and head to Fadó.
"I wanted to experience this all," he said.
Even some who weren't able to get off work found ways to follow the game. One firefighter riding in the rear of a truck called out to the crowd outside of Fadó to ask the score. People hollered back, telling him Germany held a 1-0 lead, which wound up being the final score.
While the U.S. lost, Portugal's 2-1 win over Ghana guaranteed that the U.S. would advance to the knockout stage anyway. The game is set for Tuesday. Plenty of time to come up with fresh excuses.