Facebook is using facial recognition software to let US users automatically identify friends in photos at the world's leading online social network.

A "tag suggestion" feature crafted to identify people in uploaded pictures should be rolled out to all US users in the next few weeks, Facebook engineer Justin Mitchell said late Wednesday in a blog post.

"Now if you upload pictures from your cousin's wedding, we'll group together pictures of the bride and suggest her name," Mitchell said.

"Instead of typing her name 64 times, all you'll need to do is click 'Save' to tag all of your cousin's pictures at once."

More than 100 million "tags" are added to photos at Facebook daily, according to the engineer.

When a Facebook user uploads digital pictures, newly added software matches faces to those that have been tagged, or named, in other photos, Mitchell said.

People who don't want their names automatically suggested in photo tags can disable the feature by adjusting Facebook privacy settings, according to the engineer.