Here, we bridge the gap between carbon mineralization and laundry detergent builder with sodium oxalate. Daily laundry can help mineralize carbon dioxide. First, we screen an environment-friendly process to produce sodium oxalate, using CO2 as a raw material. Then, we evaluate the properties of sodium oxalate as a detergent builder and prove the formation of calcium oxalate under laundry conditions. Our data suggest that sodium oxalate has excellent calcium-removing properties. Detergents based on sodium oxalate have good detergency. Furthermore, solid calcium oxalates (calcium oxalate monohydrate or calcium oxalate dihydrate, which has good stability in water and thermal stability), is obtained from washing waters. These results demonstrate the possibility of using sodium oxalate as detergent builder. The whole process can transform the greenhouse gas CO2 into commodity chemicals and can mineralize carbon.