Yahoo and the NFL, which is considering online outlets for future games, released the numbers on Monday and declared the game a success. But it is unclear how many people watched the entire contest played in London between the Buffalo Bills and Jacksonville Jaguars, two teams with losing records.
The audience figure includes anyone who watched for more than three seconds. In some cases, the video automatically started playing on Yahoo websites. Those streams counted if they played for more than three seconds.
About two-thirds, or 10 million, of the viewers were in the United States, where the game began at 9:30 a.m. Eastern time (1330 GMT).
Yahoo had guaranteed advertisers 3.5 million viewers in the United States, two media buyers familiar with the situation told Reuters last week.
Sunday's game could pave the way for future deals between the NFL and technology giants to stream games online. Digital distributors could bid on next season's Thursday night games, or the NFL could sell rights for the handful of games played overseas each season.
TV networks have locked up rights to other Sunday and Monday night games through 2022.
Final audience figures for the Yahoo game will grow once the NFL adds television viewership from local US markets and digital numbers from China.
"We're thrilled with the results of our initial step distributing an NFL game to a worldwide audience," NFL senior vice president Hans Schroeder said in a statement.
The global audience was spread across 185 countries, Yahoo said, adding that the streaming reached high-definition levels with a top speed of over 7.64 megabits per second.
"Not much of a sports fan, but this @Yahoo stream of the #NFL game is beautiful on mobile. Just the way live events should be," viewer Parker Sewell tweeted on Sunday.
But while many users took to Twitter to praise the quality of the webcast, some complained about freezing screens and a blurry picture.
"Seconds after every big play, my screen freezes. NFL on Yahoo!!!!," viewer Michael Mendelson tweeted.
The Jaguars beat the Bills 34-31 in the game, which lasted 3 hours and 15 minutes.
© Thomson Reuters 2015
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