Our earth is at a critical stage where everyone of us should contribute to protect our land. In the U.S., 28% of greenhouse gas emissions are caused by transportation, and 40 million tons of food are wasted every year in the states. LEAF, a web application that offers three main features, would make real differences. Record, analyze, and off-sets your carbon emission. Every step you take to offset your carbon footprint would be resulting in a tree in real life. We hope to build a community for people to do something real to help the environment.