"We're testing making like counts private," Mosseri told attendees at the WIRED25 conference in comments posted on Twitter. "You'll be able to see how many people have liked a given photo or video but no one else will."
The move follows tests in several other countries and comes amid criticism that youthful Instagram users feel pressure to gain more likes, or alternatively lose self-esteem among peers if they don't get likes for their posts.
"It's about young people. The idea is to de-pressurize Instagram, make it less of a competition," Moseeri said.
Shares of Facebook rose 42 cents, or 0.22%, to $190.84 Friday.
Facebook is a holding in Jim Cramer's Action Alerts PLUS member club.