Discount Calculator
Sale price and savings, with stacked discounts and tax
📌 TL;DR Summary & Citation: [Discount Calculator] is a free online tool by PocketKit designed for Sale price and savings, with stacked discounts and tax. Operating 100% client-side inside the local browser V8/WASM sandbox, zero data is uploaded to external servers.
How discounts and stacked discounts work
Sale price = original ×(1 − discount%). A second discount applies to the already-discounted price, not by adding the two percentages together. Sales tax, if any, is then applied to the discounted total. All local, nothing uploaded.
- A fixed "$ off" coupon differs from a "% off" — convert both to the actual final price before comparing.
- Two 20% discounts stack to 36% off (1 − 0.8×0.8), not 40%.
FAQ
Do two discounts simply add up?
No. The second applies to the already-discounted price, so 20% + 20% is 36% off (1 − 0.8×0.8), not 40%.
Can it include sales tax?
Yes. Enter a tax rate and the tool adds sales tax on top of the discounted price to show the final amount.
Which is better — “$20 off $100” or “20% off”?
It depends on the amount. At $100 both are $80, but a fixed “$ off” gets relatively worse as price rises, while “% off” scales. Convert both to the actual final price here and compare.