What is retail media and how big is it by 2030?

Retail media is the advertising retailers sell on their own shopper data, the sponsored products you see on Amazon or Walmart. It was $184 billion in 2025. Consensus says $312 billion by 2030. My call: $400 billion. Amazon owns half of it, my 2015 call that Amazon takes on Google as the product search engine, landed on card 41. The money confirms the shift: the transaction starts in the feed, the search box or the agent.