Percent Off Calculator
With original price 80 USD, discount 30 percent, extra discount on the sale price 20 percent, sales tax 0 percent, percent off comes to $44.80 — final price. It is reached in 8 steps, the last of which is net + tax_amount, and each one is printed on the page with its numbers filled in. The formula is the one published by NIST Handbook 130, not an approximation fitted to it.
The sale price after a discount, after a second discount stacked on it, and after tax — with what you actually saved.
By Alex Seote, Built and maintains Rule Calculator · Formula and sources checked · How we check
Original price 80, Discount 30, Extra discount on the sale price 20
$44.80
Final price for the example below. Editing a field recomputes the calculator below; this figure holds the answer the page was loaded with.
It is written into the HTML rather than drawn by a script, so a search engine reading this page without running JavaScript still finds an answer.
- First discount
price * discount / 100$24- Price after the first discount
price - first_off$56- Extra discount, taken off the sale price
after_first * extra / 100$11.20- Price after both discounts
after_first - second_off$44.80- You save
price - net$35.20- Effective discount
price == 0 ? 0 : saved / price * 10044 %- Sales tax on the discounted price
net * tax / 100$0- Total to pay
net + tax_amount$44.80
Ask about this in the chatCompare: one discount or twoPercent Off Chart
Worked example
A shirt at $80, marked 30% off, with a further 20% off sale prices. The first cut takes it to $56 and the second takes 20% of $56, not of $80 — so the final price is $44.80 and the effective discount is 44%, not the 50% the two signs seem to add up to.
How to work it out yourself
- 1.Enter the ticket price and the advertised discount.
- 2.If a second sign says "extra X% off sale prices", put that in the extra field. It comes off the already-reduced price, which is why the two rates do not add.
- 3.Add your local sales tax rate if you want the till figure. Every US state charges tax on the discounted price, not the original.
What each discount takes off
| Discount (percent) | Final price | You save |
|---|---|---|
| 5 | $60.80 | $19 |
| 10 | $57.60 | $22 |
| 15 | $54.40 | $26 |
| 20 | $51.20 | $29 |
| 25 | $48.00 | $32 |
| 30 | $44.80 | $35 |
| 33 | $42.88 | $37 |
| 40 | $38.40 | $42 |
| 50 | $32.00 | $48 |
| 60 | $25.60 | $54 |
| 70 | $19.20 | $61 |
| 75 | $16.00 | $64 |
On a $100 item with no second discount and no tax.
The formula
- First discount
price * discount / 100 - Price after the first discount
price - first_off - Extra discount, taken off the sale price
after_first * extra / 100 - Price after both discounts
after_first - second_off - You save
price - net - Effective discount
price == 0 ? 0 : saved / price * 100 - Sales tax on the discounted price
net * tax / 100 - Total to pay
net + tax_amount
Source: NIST Handbook 130 — Uniform Regulation for the Method of Sale of Commodities
Questions people actually ask
- Is 30% off and then 20% off the same as 50% off?
- No, and the gap is bigger than people expect. The second discount applies to the already-reduced price: $80 becomes $56, and 20% of $56 is $11.20, so you pay $44.80. A straight 50% off would be $40. The two rates never add — they multiply, and the effective discount here is 44%.
- How do I work out a percentage off in my head?
- Take 10% by moving the decimal point one place, then build the rate from it. 30% off $80 is three lots of $8, so $24 off and $56 to pay. For 15%, take 10% and add half of it. For 25%, quarter it. The arithmetic is easier from the amount saved than from the price paid.
- Is sales tax charged on the original or the discounted price?
- On the discounted price, in every US state. Tax follows the amount actually paid, so a discount reduces the tax as well as the price. Manufacturer coupons are the exception in some states — where the retailer is reimbursed, the tax can be assessed on the pre-coupon price.
- What discount takes a third off?
- A third is 33.33%, and shops usually round it to "33% off" on the sign while charging the exact third at the till. On $90 the difference is three cents. The chart row for 33% is there because it is the rate that gets advertised, not because it is the arithmetic.
- How do I find the original price from the sale price?
- Divide, do not add the percentage back. A $44.80 item that is 44% off came from $44.80 ÷ 0.56 = $80. Adding 44% to $44.80 gives $64.51, which is not the answer — the percentage is of the larger number, so the reverse operation is a division.
Related
- Percentage CalculatorWhat X% of a number is, plus the discounted price, the marked-up price and the remainder.
- Sales Tax CalculatorTax and total from a pre-tax price, plus the reverse — the pre-tax price hidden inside a total you already paid.
- Percentage Change CalculatorPercentage increase or decrease between two values, with the absolute difference and the multiplier.
- Speed & Pace CalculatorAverage speed and running pace from a distance and a time, in both imperial and metric.
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