In recent years, due to the increasingly serious carbon emission problem, global warming has become the most serious problem faced by all mankind. In order to reduce carbon emissions, the calculation of carbon footprint has become one of the most important issues. However, agricultural carbon emissions, which account for about one-third of total carbon emissions, have not received the same attention as other aspects of carbon emissions because they are not easy to evaluate. Therefore, agricultural carbon footprint calculation is not a relatively high priority. In fact, agriculture produces some key greenhouse gas emissions. As we all know, rice is the main food in Asia, but because rice cultivation methods may lead to high methane (CH4) emissions, we chose to integrate real-time methane carbon emission calculations and traditional calculation methods to develop an agricultural carbon emission calculation method as a future agricultural carbon footprint assessment tool. The carbon footprint assessment method of real-time agricultural greenhouse gas emissions that we implemented is also applicable to other agricultural greenhouse gases (GHGs), such as nitrous oxide (N2O) and carbon dioxide (CO2).