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Discount Calculator
Free discount calculator: sale price, amount saved and final price with stacked discounts and optional tax or GST added.
Applied after the first discount
Runs in your browser. Nothing you enter is uploaded.
How to use the Discount Calculator
- Enter the original price.
- Enter the discount percentage.
- Add a second discount and tax if they apply.
- Read the final price and how much you saved.
How to calculate a discount
Sale price = original price × (1 − discount ÷ 100)
A 30% discount on 2,500 saves 750 and leaves 1,750.
Stacked discounts are not added
30% off followed by an extra 10% off is not 40% off. The second discount applies to the reduced price: 2,500 → 1,750 → 1,575, a combined 37% off. Tax is added last, on the discounted price.
Spotting real deals
- Compare the final price, not the percentage.
- Check that the "original" price was ever charged.
- Include shipping and tax when comparing shops.
Frequently asked questions
How do I calculate 20% off?
Multiply the price by 0.80. For 500, the sale price is 400.
Are two discounts added together?
No. The second is taken off the already reduced price, so the combined discount is smaller than the sum.
Is tax applied before or after the discount?
After. Sales tax and GST are normally charged on the discounted price.
How do I find the original price from a sale price?
Divide the sale price by (1 − discount ÷ 100). A 1,750 price after 30% off started at 2,500.