As China is vigorously promoting “energy conservation, emission reduction, and low-carbon lifestyle”, energy conservation, emission reduction, and the response to climate warming have become important and urgent tasks for China to develop the society and economy. In order to promote the universal participation in energy conservation and emission reduction, GEM has creatively designed China’s first conservation and reduction calculator - the GEM CO2 Calculator - based on the research results of many authoritative environmental protection organizations (UNEP, EPA, NRDC, TNC, etc.) achieved in the past 30 years. Its clever design enables us to easily, conveniently, and intuitively calculate the carbon emissions from vehicles of various kinds, and quantify the carbon reduction benefiting from recycling wastes and using low-carbon and eco-friendly materials. It is an expert that can help us implement energy conservation and emission reduction initiatives.