Work out final price after a percentage discount and how much you save per item or for the whole cart.
Frequently asked questions
How do stacked discounts work?
Stacked discounts are multiplicative, not additive: 20% off plus another 20% off equals 36% total discount (0.8 × 0.8 = 0.64).
中文说明
计算打折促销后的实际到手价与单件或整单节省金额。
常见问题
多重折扣叠加如何计算？
叠加折扣是相乘而非相加：例如打 8 折再打 8 折，总折扣是 6.4 折（0.8 × 0.8 = 0.64），省 36% 而非 40%。