Quick Reference — Exact Discount Amounts
The most commonly searched discount calculations. Every cell shows the final sale price after the discount. For exact prices not shown here, use the calculator above.
| Original Price | 10% off | 15% off | 20% off | 25% off | 30% off | 40% off | 50% off |
|---|
| $5.00 | $4.50 | $4.25 | $4.00 | $3.75 | $3.50 | $3.00 | $2.50 |
| $8.99 | $8.09 | $7.64 | $7.19 | $6.74 | $6.29 | $5.39 | $4.50 |
| $10.00 | $9.00 | $8.50 | $8.00 | $7.50 | $7.00 | $6.00 | $5.00 |
| $12.99 | $11.69 | $11.04 | $10.39 | $9.74 | $9.09 | $7.79 | $6.50 |
| $19.99 | $17.99 | $16.99 | $15.99 | $14.99 | $13.99 | $11.99 | $10.00 |
| $25.00 | $22.50 | $21.25 | $20.00 | $18.75 | $17.50 | $15.00 | $12.50 |
| $49.99 | $44.99 | $42.49 | $39.99 | $37.49 | $34.99 | $29.99 | $25.00 |
| $50.00 | $45.00 | $42.50 | $40.00 | $37.50 | $35.00 | $30.00 | $25.00 |
| $75.00 | $67.50 | $63.75 | $60.00 | $56.25 | $52.50 | $45.00 | $37.50 |
| $99.99 | $89.99 | $84.99 | $79.99 | $74.99 | $69.99 | $59.99 | $50.00 |
| $100.00 | $90.00 | $85.00 | $80.00 | $75.00 | $70.00 | $60.00 | $50.00 |
| $150.00 | $135.00 | $127.50 | $120.00 | $112.50 | $105.00 | $90.00 | $75.00 |
| $200.00 | $180.00 | $170.00 | $160.00 | $150.00 | $140.00 | $120.00 | $100.00 |
| $299.99 | $269.99 | $254.99 | $239.99 | $224.99 | $209.99 | $179.99 | $150.00 |
| $500.00 | $450.00 | $425.00 | $400.00 | $375.00 | $350.00 | $300.00 | $250.00 |
| $1,000.00 | $900.00 | $850.00 | $800.00 | $750.00 | $700.00 | $600.00 | $500.00 |
How to Calculate Discounts — Every Method Explained
Whether you're shopping during a Black Friday sale, calculating a trade discount, or setting prices for your own business, understanding how discounts work mathematically helps you make smarter decisions and spot when a "deal" isn't actually a deal.
Basic percentage discount formula
Sale Price = Original Price × (1 − Discount% ÷ 100)
Example: 20% off $85 → $85 × (1 − 0.20) = $85 × 0.80 = $68 sale price. You save $17.
Reverse discount — finding the original price
Original Price = Sale Price ÷ (1 − Discount% ÷ 100)
Example: You paid $72 at 20% off → $72 ÷ 0.80 = $90 original price. You saved $18.
Finding the discount percentage from two prices
Discount % = ((Original − Sale) ÷ Original) × 100
Example: Original $120, sale price $84 → ((120 − 84) ÷ 120) × 100 = 30% off.
The truth about stacked discounts
The most common misconception in retail shopping is that two percentage discounts add up. They don't — and retailers rely on this confusion.
🧮 Real example: A $100 item with 20% off then 10% off → First: $100 × 0.80 = $80. Then: $80 × 0.90 = $72. Total saved: $28. Effective discount: 28% — NOT 30%. The gap gets larger with bigger discounts.
The formula for the effective stacked discount is: 1 − (1 − D1)(1 − D2). For 20% and 10%: 1 − (0.80 × 0.90) = 1 − 0.72 = 28% effective discount. Use the Stacked calculator tab above to see the true effective discount instantly.
Percent off vs fixed amount off — which is better?
Whether a percentage discount beats a fixed amount off depends entirely on the item's original price. There is always a crossover price where both options save the same amount:
Crossover Price = Fixed Amount ÷ (Discount% ÷ 100)
Example: Is 20% off better than $15 off? Crossover = $15 ÷ 0.20 = $75. On items under $75, the $15 off wins. On items above $75, the 20% off wins. At exactly $75, both save the same.
How BOGO deals really work
BOGO Free (buy one get one free): You pay for one item and get two. Effective discount = 50% when buying exactly two items. Only worth it if you need both items.
BOGO 50% off: You pay full price for one and half price for the second. Effective discount = 25% on your total spend.
Buy 2 Get 1 Free: You pay for two items and get a third free. Effective discount = 33.3% per item when buying three.
The key question: would you have bought the additional items at full price? BOGO deals are specifically designed to make you spend more than you planned. Use the BOGO calculator above to see the effective savings.
Does sales tax apply before or after discount?
In most jurisdictions, sales tax is applied to the discounted price, not the original price. This means your tax is calculated on what you actually pay, not on the original price. However, some specific promotions (like manufacturer coupons) may be taxed differently. Use the Discount + Tax calculator tab above to find the final price after both discount and tax.
Frequently Asked Questions
What is 20% off $50?
20% off $50 is $40. You save $10. Calculation: $50 × 0.20 = $10 discount. $50 − $10 = $40 sale price. To calculate: multiply the original price by the decimal version of the discount (20% = 0.20), then subtract from the original price.
What is 30% off $100?
30% off $100 is $70. You save $30. For any amount at 30% off: multiply by 0.70 to get the sale price directly. Or multiply by 0.30 to find the savings amount, then subtract. Example: 30% off $250 = $250 × 0.70 = $175.
What is 40% off $8.99?
40% off $8.99 is $5.39. You save $3.60. Calculation: $8.99 × 0.40 = $3.596 (rounded to $3.60). $8.99 − $3.60 = $5.39 sale price. See the full quick reference table above for more exact-amount calculations.
How do I find the original price before a discount?
Divide the sale price by (1 minus the discount as a decimal). Formula: Original = Sale ÷ (1 − discount%). Example: paid $80 at 20% off → $80 ÷ 0.80 = $100 original. Use the Original Price tab in the calculator above for instant results.
Do stacked discounts add up?
No — stacked discounts never simply add up. 20% off + 10% off = 28%, not 30%. The second discount applies to the already-reduced price. The more discounts stack, the bigger the gap. Use the Stacked Discounts tab to find the true effective discount for any combination.
Is 30% off better than $20 off?
It depends on the original price. The crossover point is $66.67. Below $66.67 the $20 off wins. Above $66.67 the 30% off wins. On a $50 item: 30% saves $15 (dollar off wins). On a $100 item: 30% saves $30 (percentage off wins). Use the Compare Deals tab to find which is better for any price.
How does BOGO work and how much do I actually save?
BOGO Free: pay for one, get two — effectively 50% off per item. BOGO 50% off: pay full for one, half for second — effectively 25% off total. Buy 2 Get 1 Free: effectively 33% off per item when buying three. The effective savings are always less than they sound — use the BOGO Calculator tab above to see the real discount for any deal.
Is tax calculated on the original price or the discounted price?
In most countries and US states, sales tax is calculated on the discounted (sale) price, not the original price. This means you save tax on the discount as well. Some exceptions apply with manufacturer coupons. Use the Discount + Tax tab above to calculate the exact final price with both discount and tax applied.
How do I calculate a percentage discount?
To calculate a percentage discount, multiply the original price by the discount percentage and divide by 100 to get the savings. Then subtract from the original price. Formula: Sale Price = Original Price × (1 − Discount% ÷ 100). Example: 20% off $50 → $50 × 0.80 = $40 sale price. You save $10.
Do stacked discounts add up? Is 20% off plus 10% off the same as 30% off?
No — stacked discounts do NOT add up. 20% off plus 10% off equals 28% total, not 30%. The second discount applies to the already-reduced price. On a $100 item: 20% off gives $80, then 10% off $80 gives $72. Total saving = $28, not $30.
Is it better to take percent off or dollars off?
It depends on the original price. Percent off is better on expensive items; fixed dollar off is better on cheaper items. Example: 20% off vs $15 off. On a $50 item: 20% saves $10 (dollar off wins). On a $100 item: 20% saves $20 (both equal at $75 crossover). Above $75, percent off wins. Use the Deal Comparison calculator to find the crossover point instantly.
How do I calculate discount percentage from two prices?
Formula: Discount % = ((Original Price − Sale Price) ÷ Original Price) × 100. Example: Original $120, sale price $90 → ((120 − 90) ÷ 120) × 100 = 25% off.
How does a BOGO deal work?
BOGO (Buy One Get One) Free means the second item is free — effectively 50% off per item when buying two. BOGO 50% off means the second item is half price — effectively 25% off your total. Buy 2 Get 1 Free gives 33% off per item when buying three. Use the BOGO calculator tab to compare any BOGO deal.
How do I calculate the original price before a discount?
Divide the sale price by (1 - discount%/100). If an item is £60 after a 25% discount: £60 / 0.75 = £80 original price. This reverse calculation is useful for finding the pre-sale price from a discounted tag. The calculator above handles this automatically in the reverse discount tab.
Related Calculations
Discount calculations are part of a wider set of percentage and pricing tools:
→ Percentage Calculator — Calculate what percentage one number is of another, percentage change and more.
→ Profit Margin Calculator — If you're a seller, see how discounts affect your profit margins before offering them.
→ VAT Calculator — Add or remove VAT/GST from any price for 27+ countries.
→ Tip Calculator — Calculate how much to tip at restaurants, for delivery, Uber and more.