🏷️Discount Calculator
Find your savings, work backwards from a sale price, or compute stacked discounts correctly.
Runs entirely in your browser. No data is sent to a server.
Free Discount Calculator
Trying to work out how much you'll actually save — or pay — on a discounted item? Our free discount calculator does the math instantly. Enter the original price and discount percentage to see your savings and final price, or work backwards from a sale price to find the original.
It also correctly handles stacked discounts — like "20% off, then an extra 10% off at checkout" — compounding each discount on the already-reduced price instead of simply adding the percentages, which is a common mistake that overstates your savings. Every calculation shows the formula and step-by-step working, so you can see exactly how the final number was reached.
No sign-up, no downloads, no limits — just accurate discount math whenever you're shopping or pricing a sale. See the About page or the FAQ for more.
About the Discount Calculator
Why stacking matters
A common mistake is adding stacked percentages together (20% + 10% = 30%). Each discount actually applies to the running price, so 20% then 10% off $100 gives $100 × 0.8 × 0.9 = $72, not $70. The calculator shows the running price after each step.
Frequently Asked Questions
How does the discount calculator work?
Enter the original price and discount percentage; it shows your savings and the final price.
Is it free?
Completely free, no sign-up or limits.
Can it work backwards from the sale price?
Yes, the reverse mode finds the original price given a discounted price and the percentage applied.
What are stacked discounts?
Multiple discounts applied one after another (e.g. 20% then an extra 10%) — each discount applies to the already-reduced price, not the original, so the total savings is less than simply adding the percentages.
Why isn't 20% + 10% the same as 30% off?
Because the second discount applies to the price after the first discount, not the original price — the calculator shows this compounding step by step.
Does it show the calculation formula?
Yes, the formula and substituted values are shown for every mode.
Can I enter more than two stacked discounts?
Yes, add as many successive discount percentages as needed.
What if I enter a discount over 100%?
The calculator validates this and blocks the input with a clear message.
Is my data stored?
No; everything runs in your browser and isn't stored or sent.
Does it work on mobile?
Yes, fully responsive.