Percent Off Calculator
Enter a price and a percent off — the sale price and your savings appear instantly, including stacked 'extra % off' deals.
Reverse: what percent off is this?
The Percent Off Formula
A percent-off price is the original price scaled by the share you still pay. If P is the price and d the percent off:
You pay = P × (1 − d/100) · You save = P × d/100
So 25% off means paying 75%: $80 × 0.75 = $60, a saving of $20. The table below pins down the common cases on a $100 item:
| Percent off | You pay (of $100) | You save |
|---|---|---|
| 10% | $90.00 | $10.00 |
| 15% | $85.00 | $15.00 |
| 20% | $80.00 | $20.00 |
| 25% | $75.00 | $25.00 |
| 30% | $70.00 | $30.00 |
| 40% | $60.00 | $40.00 |
| 50% | $50.00 | $50.00 |
| 75% | $25.00 | $75.00 |
The Stacked-Discount Trap
"20% off — plus an extra 10% off at checkout!" feels like 30% off. It isn't. The second percentage comes off the reduced price: $100 → $80 → $72. The real combined discount is 28%, and on a $500 purchase the gap between the promised-feeling 30% ($350) and the actual 28% ($360) is $10. Successive percents always multiply rather than add — (1 − 0.20) × (1 − 0.10) = 0.72 — which is why the calculator above takes the extra discount as its own input and reports the effective total percent off, the number the store's banner won't tell you.
Percent Off vs the Discount Calculator
This page is the quick, single-purpose tool: a price, a percentage, an answer, plus the reverse question (two prices → what percent?). Its twin, the Discount Calculator, goes further with tax-inclusive totals and multi-item baskets. For the general-purpose tool — percentages of numbers, increases and decreases — use the Percentage Calculator; for tax itself, the Sales Tax Calculator.
Frequently Asked Questions
How do you calculate percent off?
Multiply the original price by the percentage taken off, then subtract — or equivalently, multiply by what's left. 25% off $80: the discount is 80 × 0.25 = $20, so you pay $60. The shortcut is to multiply by (1 − 0.25) = 0.75 directly: 80 × 0.75 = $60. This calculator does it either way and shows both the amount saved and the price you pay.
What is 20% off $50?
20% off $50 is $40 — you save $10. The discount is 50 × 0.20 = $10, and 50 − 10 = $40. Equivalently, paying 80% of the price: 50 × 0.80 = $40.
How do stacked discounts work — is 20% off plus an extra 10% off the same as 30% off?
No, and the difference is real money. The second discount applies to the already-reduced price, not the original. On $100: 20% off leaves $80, then an extra 10% off $80 leaves $72 — a total saving of 28%, not 30%. True 30% off would be $70. Stores know the stacked version sounds bigger than it is; this calculator has a dedicated 'extra % off' box so you can see the true combined discount.
How do I work out the percent off from two prices?
Subtract the sale price from the original, divide by the original, and multiply by 100. A jacket marked down from $85 to $63.75: the saving is $21.25, and 21.25 ÷ 85 = 0.25, so it is 25% off. The second calculator on this page does exactly this — enter the original and sale prices and it returns the percentage.
Does percent off apply before or after tax?
In most US stores the discount comes off first and sales tax is charged on the reduced price — so a percent-off deal also shrinks the tax a little. The exact rule varies by state and by coupon type (manufacturer coupons are sometimes taxed on the full price). This calculator shows the price before tax; add your local rate to the discounted price for the register total.
What is the difference between percent off and percentage points?
Percent off is relative to the price: 20% off $50 removes $10. Percentage points are an absolute difference between two percentages — an interest rate falling from 5% to 4% dropped by 1 percentage point, which is a 20% relative fall. Sale tags always mean relative percent off the price.
Is this percent off calculator free?
Yes. It is completely free with no signup required, and it runs entirely in your browser — the prices you enter are never uploaded or stored.