The data comes from the research firm's TotalWeb report which integrates data from Nielsen Mobile and Nielsen Online to show unduplicated, unique audiences for more than 200 leading internet sites across the PC and mobile internet space.
"The data demonstrates that the mobile internet can not only increase the frequency of visits to a website, but grow the overall size of the pie," said Jeff Herrmann, vice president of mobile media at Nielsen Mobile.
"Publishers can now monetise their total cross-platform audience, and advertisers will better understand the efficiency and incremental value of mobile web traffic."
The report said that 87 million US mobile users subscribe to mobile internet services, and 13.7 per cent of mobile subscribers actively use mobile internet each month.