A Pew Research Center survey released Thursday found that 92 percent of US teens go online daily.
That includes 56 percent who are online several times a day and 24 percent who say they are connected to the Internet and social networks "almost constantly."
A key factor is the growing prevalence of smartphones.
The survey of teens between the ages of 13 and 17 found that 73 percent had a smartphone and 30 percent had at least a basic cellphone.
Even though 87 percent of teens have access to a computer, 91 percent went online daily using a mobile device at least occasionally, Pew found.
The survey found that African-American and Hispanic youth are among the most active Internet users.
Among African-American teens, 34 percent reported going online "almost constantly" as did 32 percent of Hispanic youth and 19 percent of white teens.
"American teens, especially African-American youth, have embraced smartphones and the 24/7 access to people and information that they offer," said Amanda Lenhart, a Pew researcher and the lead author of the report.
Some 90 percent of teens with phones exchange text messages, with a typical teenager receiving 30 texts per day, Pew found. And one-third of those with smartphones use messaging apps such as WhatsApp or Kik.