Firms have increasingly relied on digital platforms to direct consumers to their products, with digital advertising becoming a major source of revenue for big tech companies, often allowing them to offer free access to their platforms. Who hasn’t noticed the ads targeted at their interests while shopping online or scrolling their social media feed? Despite the growing importance of the sector, data on the digital advertising market are scant. In this blog post, we present some estimates of the importance of digital advertising in the U.S. and discuss its macroeconomic impact.