Inventory forecasting is the practice of predicting the future availability of ad inventory on a website or app. Inventory forecasting is typically used by advertisers and publishers to plan and execute their advertising campaigns, and to ensure that they have access to the right amount of inventory at the right time. Inventory forecasting involves analyzing a variety of data, such as historical traffic patterns, seasonality, and trends, in order to make accurate and informed predictions about future inventory availability. Inventory forecasting can be a valuable tool for advertisers and publishers, as it can help them to optimize their ad spend and revenue, and to avoid overselling or underselling their inventory.