glunty Discount Calculator (Sale Price + Percent Off)
Percent off to final price and amount saved. Stack discounts and add tax.
- Runs in your browser
- No sign-up
- No watermark
- No installs
Breakdown
Reverse: find the discount percent
Have the original and the sale price? Get the percent off.
What this tool does
Works out the sale price and the amount saved when something is marked down by a percentage. Enter the original price and the discount percent and it shows the final price live. You can stack a second discount (applied to the already-discounted price, the way real coupon stacking works) and add a sales-tax percent, which it applies after the discount to give a final total. A reverse helper goes the other way: give it the original and the sale price and it returns the percent off. Everything runs in your browser; nothing is uploaded.
How to use it
Type an original price and a discount percent; the sale price and amount saved update as you type. Leave the second discount and tax fields blank if you do not need them. Example: 100 at 25% off gives a sale price of 75.00 and 25.00 saved. Add a second 10% off and it becomes 67.50 (an effective 32.5% off, not 35%, because the second cut applies to the 75.00, not the original). To go backwards, use the reverse box: an item marked down from 80 to 60 is 25% off.
Common use cases
- Checking a storefront markdown before you buy: what does "40% off" actually cost?
- Stacking a sale price with a coupon code to see the true combined discount.
- Adding sales tax to a discounted cart so the final total holds no surprises.
- Reverse-engineering the percent off from a "was 80, now 60" price tag.
- Comparing two deals by amount saved in real money, not just headline percentages.
Common pitfalls
- Stacked discounts multiply, they do not add. 25% off then 10% off is 32.5% off, not 35%. Each discount applies to the running balance, so two coupons are always worth a little less than their sum suggests.
- Tax comes after the discount. In most places sales tax is charged on the discounted price, which is what this tool assumes. If a local rule taxes the pre-discount amount, treat the total as an estimate.
- Percent off is not the same as amount saved. A 30% discount on a cheap item can save less real money than a 10% discount on an expensive one. When comparing deals, look at the amount saved, not just the headline percentage.
Frequently asked questions
- How do I calculate a sale price from a percent off?
- Multiply the original price by the discount, then subtract that from the original. A shortcut: multiply the original by (100 minus the percent), divided by 100. For example, 25 percent off a price of 100 is 100 times 0.75, which equals a sale price of 75, an amount saved of 25. This tool does that arithmetic live as you type and also shows the amount saved so you can sanity-check the deal.
- Are two stacked discounts the same as adding the percentages?
- No, and this trips a lot of people up. Stacked discounts apply one after another, each to the running balance, so they multiply rather than add. Taking 25 percent off then 10 percent off a price of 100 gives 100 times 0.75 times 0.90, which is 67.50, an effective 32.5 percent off, not 35 percent off. Adding the percentages would overstate the saving. The tool computes the true combined figure and reports the effective discount for you.
- Should sales tax be applied before or after the discount?
- In almost every jurisdiction, sales tax is charged on the discounted price, not the original. That is why this tool applies the tax percent after both discounts, on the final sale price. If your local rule differs (a few places tax coupons or rebates differently), treat the output as an estimate and confirm with your receipt or local tax authority.
- How do I work out the discount percent from the original and sale price?
- Subtract the sale price from the original, divide by the original, then multiply by 100. For example, an item marked down from 80 to 60 is (80 minus 60) divided by 80, times 100, which is 25 percent off. Use the reverse helper at the bottom of the tool: enter the original and the sale price and it returns the percent off and the amount saved.
- What is the difference between amount saved and the final price?
- The final sale price is what you actually pay before tax; the amount saved is how much lower that is than the original sticker price. They always add up to the original: sale price plus amount saved equals the original price. Retailers advertise the percent off, but the amount saved in real money is often the more useful number when comparing two deals on differently priced items.
- Why is 50 percent off twice not the same as 100 percent off?
- Because the second 50 percent is taken off an already-halved price, not the original. Fifty percent off 100 is 50, and 50 percent off that 50 is 25, so you pay 25 and save 75, an effective 75 percent off, not free. Any two stacked discounts short of a single 100 percent off will always leave something to pay. The tool makes this concrete by showing the running balance after each discount.
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