Pinterest forecast first-quarter revenue above market estimates on Thursday, betting on the image-sharing platform's artificial intelligence-powered advertising tools to boost ad spend, sending its shares up 22% in extended trading.

The advertising business continues to grow despite increased competition from much larger rivals in the social networking space.

As well as hitting $1 billion in quarterly revenue for the first time, Pinterest reached record user numbers, with 553 million monthly visits.

Pinterest PINS hit fourth-quarter sales of $1.15 billion, coming in above $1 billion for the first time, and grew the number of its global monthly active users by 11% year-on-year to 553 million. It also guided for better-than-expected revenue in the current quarter.