Consume is a decision-making tool designed to assist resource managers in planning for wildland fire events (e.g., prescribed fires and wildfires). Consume predicts fuel consumption, pollutant emissions, and heat release based on fuel loadings, fuel moisture, and other environmental factors. Using these predictions, resource managers can determine when and where to conduct a prescribed burn or manage an unplanned wildland fire to achieve desired objectives while reducing the impact on other resources. Consume 4.2 reflects an improved understanding of fuel consumption and emissions in wildland fire throughout major fuel types in the United States. Fuel consumption is a key variable in fire effects modeling and in understanding when and how fire should be applied to meet site and landscape objectives while at the same time reducing air quality impacts. Until recently, much of the considerable research on fuel consumption focused on prescribed burning following logging in forested ecosystems. FERA recently completed several fuel consumption studies in natural fuel settings to improve understanding of fuel consumption in wildland fuels for shrublands (including chaparral, sageland and palmetto/galberry types), hardwood forests (including southern and eastern regions of the United States), and boreal forests (including white spruce, black spruce and hardwood forests of Alaska). Improved models of fuel consumption were incorporated into Consume v 3.0. Also, differences in fuel consumption were resolved between the relatively short flaming phase of combustion and the longer smoldering phase of combustion that generally contributes the majority of wildland fire emissions. Consume 4.2 has been recoded as a calculator module that can be used within the Fuel and Fire Tools or as a command line version. The python source code is a freely sharable module that has been incorporated into BlueSky and the Wildland Fire Emissions Inventory System. An earlier version (Consume 4.0) has been included in the Integrated Fuel Treatment Decision Support System (IFTDSS) but has not been fully tested and does not return the same values as Consume 4.2.