Purpose We investigated the energy usage, economics, and global warming potential (GWP) of spring rice production via farm sizes in Nepal. Methods Seventy farmers were selected via purposive sampling methods, and data were collected by interviewing the farmers on site. Results It was found that 22,987 mega joules of energy per hectare (MJ/ha) was invested in order to yield 77,355 MJ/ha worth of outputs (5262 kg/ha). The analysis shows that the highest share of energy input was contributed by machinery (33.50%) and least by chemicals (0.96%). It was further found that spring rice farming in Nepal is less energy productive (0.23 kg/MJ) and less energy efficient (3.37) than that of neighboring countries-such as India, China, and Pakistan. The total GWP is estimated about 720.56 kg CO 2 eq/ha. The average cost of production was found to equate to USD810.24/ha (or USD0.154/kg of production), and that profit only reached USD73.93/ha. Conclusion This study found that energy use, cost of production, and yield per ha all generally decrease as the size of the landholding increases, whereas energy use efficiency and profits increase to an optimum level of land size and inputs. Low profits could be the result of the small size of landholdings and low levels of mechanization. This can be improved by increasing energy inputs and practicing community-farming.