Instagram announced said it will soon allow advertisers to buy carousel ads on a self-service basis.<br />The Facebook-owned company will let advertisers buy the ads through its Ads API, Power Editor, and Ads Manager interfaces.<br />Companies will be able to manage campaigns using Facebook's Ads Manager within the next few weeks, Instagram said.<br />"By opening up the way advertisers can buy, businesses of all sizes around the world now have more flexible targeting, call-to-action button options, and can customize their offsite links to help drive maximum return," Instagram said in a blog post today.<br />Instagram has grown from nothing in 2010 to a user base of 400 million people worldwide, 77 million of whom are in the U.S. Facebook bought Instagram for $100 million back in 2012.