Coupon Savings Calculator

Coupons and promo codes come in enough shapes that it is often genuinely unclear what you are saving, especially once two discounts stack and the order they apply in starts to matter. This calculator gives you the final price and the real saving for each type.

Types of Discounts

Percentage Off (% off) The most common format. A “20% off” coupon means you pay 80% of the original price. Formula: Savings = Original Price × (Discount % / 100) Final Price = Original Price × (1 − Discount % / 100)

Dollar Off ($X off) A flat dollar amount is deducted from the original price. Formula: Final Price = Original Price − Dollar Discount This is a better deal on small purchases; percentage-off is better on large purchases.

Buy One Get One (BOGO) BOGO Free: You pay for one item and get a second free. Effective discount = 50%. BOGO 50% Off: You pay full price + half price. Effective discount = 25%. BOGO is only worthwhile if you actually need two of the item.

Stacked Discounts Many stores allow stacking a store coupon with a manufacturer coupon, or applying a loyalty discount before a promo code. Stacking is applied sequentially:

Example: $100 item, 20% off then $10 off:

1. Apply 20% off: $100 × 0.80 = $80
2. Apply $10 off: $80 − $10 = $70 final price

If applied in reverse ($10 off first, then 20% off):

1. $100 − $10 = $90
2. $90 × 0.80 = $72 final price

Order matters. Apply the percentage first, then the dollar amount, and you keep an extra $2 on this example. Some checkouts let you choose; most do not, and apply them in whatever order the system prefers.

Is the Coupon Actually Worth It?

A coupon is only worth anything if you were going to buy the item regardless. Buy a $50 thing you do not need with a 30% coupon and you have not saved $15. You have spent $35.

Extreme Couponing Tips

• Stack manufacturer + store coupons when allowed
• Combine with cashback apps (Ibotta, Rakuten)
• Wait for sale + coupon combos for maximum savings
• Check expiry dates, expired coupons are worthless