The World Food Programme (WFP) estimates the increase in acute hunger following the Ukraine conflict. It models the pass-through of price increases on global grain and energy markets from international to domestic markets, and the ensuing loss of access to food by those who could barely afford a minimal diet before the conflict-driven price rises. We examine two scenarios: for the conflict ending within the next month, and continuing beyond April 2022. For the 81 countries with WFP operations, we find that acute hunger will rise by an additional 33 million people in the first scenario and an additional 47 million people in the second scenario, from a pre-war baseline of 276 million people who were already in the grip of acute hunger. Altogether, this means that up to 323 million people could become acutely food insecure in 2022.