The use stage of a textile product impacts sustainability more significantly than other stages of the product’s life cycle due to repeated washing and drying. This study determines efficient washing conditions, with high detergency, to reduce energy consumption from excessive washing and improve the washing process sustainability. Detergency was measured at various washing temperatures (20°C, 40°C, and 60°C) and time (10 min, 20 min, and 30 min) using standardized soiled fabrics, i.e., 100% cotton, polyester/cotton (65%/35%), and 100% polyester woven fabric soiled with pigment/sebum, carbon black/mineral oil, soot/mineral oil, cocoa, blood, and red wine. Detergency at the washing condition of 20 ℃ and 30 min was higher than that at 40 ℃ and 10 min. In addition, detergency at the condition of 40 ℃ and 30 min was also higher than that at 60 ℃ and 10 minutes. This may be because a reduced washing effect at low washing temperatures was complemented by increased mechanical action over a long time. Further, washing temperature and time, with the same detergency, differed based on the type of fiber and soil. Also, the influence of a detergent on the detergency depends on the type of soil. The results suggest that energy and detergent have been consumed more than necessary in actual laundry. According to each type of fiber and soil, washing conditions designed to reduce the energy consumption of the washing process while maintaining the same detergency, were determined.