The age limit had previously been 18, but Google vice president for product management Bradley Horowitz announced on Google+ that users could now be as young as 13.
Facebook, the world’s leading social network with more than 800 million members, also has an age limit of 13.
Horowitz said Google+ is implementing several safety features aimed specifically at teens.
“With Google+, we want to help teens build meaningful connections online,” he said in a post on his Google+ account. “We also want to provide features that foster safety alongside self-expression.”
Google+ organizes online connections into circles such as friends and family and one of the safety features is a reminder to a teen whether they really want share a post publicly outside of their circles.
Horowitz said Google+ is also giving teen users “control over who can contact them online.
“By default, only those in teens’ circles can say hello, and blocking someone is always just a click or two away,” he said.
“Between strong user protections and teen-focused content, it’s our hope that young adults will feel at home (and have some fun) on Google+,” Horowitz said.
On Tuesday, Google+, which had been insisting that users go by their legal names, began allowing users to use nicknames or established pseudonyms such as Madonna.
“Over the next week, we’ll be adding support for alternate names — be they nicknames, birth names, or names in another script — alongside your common name,” Horowitz said.
He described the move as a “small step towards improving the ways in which you can communicate your identity on Google+.”
Google+, which launched last year, has attracted more than 90 million users, Google chief executive Larry Page said last week.