Money & everyday · 3 min read
How to Calculate a Discount and Sale Price (Stacked Too)
One discount
Multiply the price by the discount percent to get the saving, then subtract it. Or multiply by the remaining fraction in one step.
25% off 80
- Sale price before tax: 60.00
Step-by-step working 2 steps
- 1First discount
80 × 25% = 20 80 − 20 = 60
Discount amount = price × percent ÷ 100, then subtract it.
- 2Round to cents
Final price 60.00, you save 20.00 (25% of the original)
Two discounts do not add
20% then another 10% on 100 is Pay 72.00 · Save 28.00, which is 28% off in total — not 30% — because the second discount applies to the reduced price.
20% then 10% off 100
- Sale price before tax: 72.00
Step-by-step working 3 steps
- 1First discount
100 × 20% = 20 100 − 20 = 80
Discount amount = price × percent ÷ 100, then subtract it.
- 2Extra discount (applied to the reduced price)
80 × 10% = 8 80 − 8 = 72
Stacked discounts multiply; they do not simply add. 20% then 10% is 28% off in total.
- 3Round to cents
Final price 72.00, you save 28.00 (28% of the original)
Adding sales tax
Tax is normally charged on the discounted price. 10% off 100 plus 8% tax: Pay 97.20 · Save 10.00.
Quick mental method
For 30% off, find 10%, triple it, subtract. Try the discount calculator, or work backwards with reverse percentages.
Frequently asked questions
How do I calculate 20% off?
Multiply the price by 0.8.
Is 50% off then 50% off free?
No — it is 75% off in total (25% of the price remains).
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