How do you calculate a double discount?
30% off followed by another 10% off is a 37% total discount. On an original price of 5,000, calculate 5,000 × 0.7 × 0.9 = 3,150. You save 1,850. The second discount applies to the already-reduced price, so adding 30 and 10 overstates the saving.
Use the discount calculator to enter an original price, a first discount and an additional discount together. It shows the final price, total savings and effective rate.
Double discount formula
Let P be the original price and a and b be the two discount percentages. Enter percentage numbers such as 30 and 10 for a and b.
- Final price = P × (1 − a / 100) × (1 − b / 100)
- Effective discount (%) = a + b − a × b / 100
- Savings = original price − final price
For 30% and 10%, 30 + 10 − 30 × 10 / 100 = 37%. For 20% and 10%, 20 + 10 − 20 × 10 / 100 = 28%.
Common double discount combinations
These examples apply two percentage discounts sequentially with no intermediate rounding. Use the same currency unit for the original and final prices.
| First discount | Second discount | Effective discount | Final price on 10,000 |
|---|---|---|---|
| 10% | 10% | 19% | 8,100 |
| 20% | 10% | 28% | 7,200 |
| 20% | 20% | 36% | 6,400 |
| 30% | 10% | 37% | 6,300 |
| 30% | 20% | 44% | 5,600 |
| 50% | 20% | 60% | 4,000 |
Use the double discount calculator
- Open the discount calculator and enter
5000for the original price. - Enter
30for Discount rate and10for Additional discount. - Check the effective rate of 37%, savings of 1,850, and final price of 3,150.
For one discount, leave Additional discount empty. It accepts 0–100%. The tool handles percentage discounts; it has no fixed-amount coupon or points field. It rounds displayed results to at most two decimal places, without rounding between discounts.
Triple discount example: 43.3% off
For 30% off, then 10% off, then another 10% off, multiply three remaining-price factors:
5,000 × 0.7 × 0.9 × 0.9 = 2,835
You pay 56.7% of the original price, so this is a 43.3% discount, not 50%. To calculate the third step in the tool, enter 3,150 as a new original price, set the rate to 10%, and clear Additional discount. That screen’s rate describes only the new 10% step. For the total relative to the original price, calculate (5,000 − 2,835) / 5,000 × 100 = 43.3%.
Reward points are different from money off today
Points earned on this purchase do not automatically reduce today’s checkout total. Suppose an item costs 10,000, is discounted by 20%, and earns points worth 8% of the discounted 8,000 price.
- Paid at checkout: 8,000
- Points earned later: 640 points, assuming each is redeemable for one currency unit
- Value-adjusted cost if all points are used later: 7,360
The checkout price is not 7,360. Earning increments, caps, expiration and redemption conditions can change the value. If you redeem points you already hold, check the store’s rules for applying them to this purchase separately.
Does the order of discounts matter?
For percentage discounts applied to the same whole price, with no intermediate rounding, changing the order gives the same result: 0.7 × 0.9 = 0.9 × 0.7.
Fixed-amount coupons behave differently. For an original price of 5,000 with 20% off and a 500-off coupon:
- 20% off, then 500 off:
5,000 × 0.8 − 500 = 3,500 - 500 off, then 20% off:
(5,000 − 500) × 0.8 = 3,600
Whether coupons stack, minimum spend, eligible items and rounding depend on the store. Check the actual checkout total against those conditions.
Frequently asked questions
Are two 20% discounts equal to 40% off?
They give 36% off. 0.8 × 0.8 = 0.64, so you pay 64% of the original price.
Is 30% off plus 10% back in points a 37% discount?
You still pay the price after the 30% discount. If points worth 10% of that entire amount are earned and fully redeemed later, the value-equivalent saving is 37% of the original price. That is different from receiving 37% off in cash at checkout.
How does rounding work?
The calculator keeps unrounded values between the discounts and displays at most two decimal places. A store that rounds or truncates at each step can produce a different result. Store-specific rounding rules are not configurable in this tool.
For a single sale, read the discount calculation guide. For percentages more broadly, see the percentage guide.
