Discount Calculator
Find the final price and savings on any discount. Reverse-mode works backwards from a sale price to the original. Stacked discounts supported.
Runs in your browser — nothing uploaded
Original price + discount
Three discount questions in one place. Find what you pay after a percent off, work backwards from a sale price to the original price, or stack multiple discounts to see the equivalent single percent off. Handy at checkout, while shopping, or when running a sale.
Private by design — your data never leaves your device
How to use it
No account, no upload — it all happens on your device.
1
Pick a mode: 'Find sale price', 'Find original price', or 'Stacked discounts'.
2
Type the price and the discount percent — switch the currency from the dropdown if needed.
3
Read the highlighted answer at the bottom: the price you pay and how much you save.
4
In stacked mode, add as many percent-off steps as you need; the tool shows each step's running total.
The three discount questions
Each maps to one mode in the tool.
| Question | Mode | Example |
|---|---|---|
| What do I pay? | Find sale price | $80 with 25% off = $60.00 |
| What was the original price? | Find original price | $60 sale, 25% off → was $80.00 |
| What's the effective discount across coupons? | Stacked discounts | 20% then 10% = 28% off, not 30% |
Why stacked discounts surprise people
- Multiplicative, not additive. Two discounts applied one after another multiply their remainders, so 20% off then 10% off keeps 0.8 × 0.9 = 0.72 of the price. The final discount is 28%, not 30%.
- Order doesn't matter for percentage discounts: 20% then 10% lands on the same final price as 10% then 20%. Both reduce the price to 72% of the original.
- But fixed-dollar coupons do depend on order.A $10 coupon followed by 20% off is different from 20% off followed by a $10 coupon — the second one applies the percent to a larger amount and saves you more. This tool handles percent-only stacks; for mixed stacks, run them as two forward calculations.
Watch-outs while shopping
- Anchor pricing.A "50% off" tag is only meaningful if the "original" price was ever real. Quickly check the typical price elsewhere before celebrating the deal.
- Pre-tax vs post-tax. Discounts almost always apply to the pre-tax price. Sales tax is then added to the discounted total.
- Coupons with thresholds."$20 off $100+" is a 20% discount at the threshold, less above it, and not usable below. Compare against a flat percent if both are offered.
Frequently asked
How do I work out a percent off a price?
Multiply the price by the discount percent divided by 100 — that's how much you save. Subtract from the original price to get what you pay. The 'Find sale price' tab does both at once.
Why isn't '20% off then 10% off' the same as 30% off?
Each discount applies to the price after the previous one, not to the original. 20% then 10% leaves you paying 0.8 × 0.9 = 72% of the original — a 28% effective discount, not 30%. The 'Stacked discounts' tab shows this step by step.
Is my price data sent anywhere?
No. The calculator runs in your browser as plain multiplication and subtraction. No prices, percentages, or anything else you type leaves your device.