20% off, then another 10% off
100 × 0.80 × 0.90 = 72
The first discount saves 20. The second saves 10% of 80, which is 8. The combined percentage discount is 28%, not 30%.
Prices and percentages
Discount Calculator
Combine two discounts and a coupon, then compare them with a single discount.
Calculate a discounted price
Discount result
Enter a price and discount, then select Calculate.
Final price
Offer B · final price
- Offer B savings
- Price difference
Amounts use the same currency or unit as your original price.
Price breakdown
- After first discount
- After additional discount
- Combined percentage rate, excluding coupon
- Coupon actually applied
- Total saved, including coupon
Values are displayed to 2 decimal places. ≈ marks rounding. Offers are compared before display rounding.
Your inputs are processed in your browser and are not sent to a server.
Discount examples
Subtract a coupon of 5 after those discounts
72 − 5 = 67
The final price is 67, and total savings are 33. The percentage-only rate remains 28%; it excludes the coupon.
Would a single 30% discount be cheaper?
100 × 0.70 = 70
A single 30% discount gives a price of 70. The combined offer with the coupon costs 67, so it is 3 cheaper.
Use the result to choose an offer
Compare final prices when stores start at different prices. The comparison field above uses one original price for both offers. For the same item listed at 80 in one store and 100 in another, run each separately: 20% off 80 gives 64, while 30% off 100 gives 70. The smaller discount saves you 6 on the purchase because it starts from a lower price. Leave the additional discount and coupon blank when they do not apply.
Add delivery costs before deciding. In the worked example above, Offer A costs 67 and Offer B costs 70 before shipping. Suppose A charges 6 for delivery and B offers free delivery, with no other charges. The totals become 73 and 70, so B is now 3 cheaper. Shipping is not entered in this calculator; add the quoted charge to each result separately.
Compare the same purchase. Check that the item, quantity, and currency match and that you qualify for every reduction. For different package sizes, compare the discounted price per unit with the Unit Price Calculator. A lower package price alone does not tell you which offer buys more for your money.
Formulas and rounding
For original price P, first discount a, and additional discount b, the price after the percentages is P × (1 − a/100) × (1 − b/100).
The combined percentage rate is 100 × [1 − (1 − a/100) × (1 − b/100)]. It depends on the two rates and excludes the coupon. Total savings are the original price minus the final price after the coupon.
The applied coupon is the smaller of the entered coupon and the price remaining after both percentages. The final price cannot be negative. Any part of a coupon that cannot be applied is shown as unused.
Calculations use decimal arithmetic with 60 significant digits and no intermediate rounding. Displayed amounts and rates are rounded to 2 decimal places, with exact halfway values rounded away from zero. Displayed steps can therefore differ slightly when added together. An actual checkout may round at different steps.
Common questions
Why do two percentage discounts not simply add together?
The second percentage applies to a smaller amount. For example, two discounts of 50% leave 25% of the original price: 100 × 0.50 × 0.50 = 25. That is a combined discount of 75%.
Does the order of the discounts matter?
Reversing two percentage discounts produces the same final price when there is no intermediate rounding. A flat coupon is different: for a price of 100, taking a coupon of 5 first, then 20% and 10% off, gives (100 − 5) × 0.80 × 0.90 = 68.40. Taking the coupon last gives 67. This calculator always applies the coupon last, so check the store's stated order before using its result.
What happens if my coupon exceeds the remaining price?
The final price stops at zero. For example, after a price of 100 is reduced by 20%, a coupon of 100 can only reduce the remaining price by 80. The calculator shows 80 applied and 20 unused. It does not treat the unused part as cash or credit.
How do I compare an offer with no discount?
Enter 0 in the single-discount comparison field. That compares the combined offer with the original price. Leave the field blank to turn comparison off. The comparison offer never includes the additional discount or coupon.
Can I use a zero price or a 100% discount?
Yes. Prices and coupons must be nonnegative, and percentage discounts must be between 0 and 100. At a zero original price, all price amounts and savings are zero. The combined percentage rate is still calculated from the entered rates without dividing by the price.
Does this calculate the total I will pay at checkout?
It calculates the original price after the specified discounts and coupon. Taxes, shipping, currency conversion, discount eligibility, and store-specific rounding are outside its scope. Use the same currency or unit for the original price and coupon.