Calculate Discounts and Sale Prices Instantly
Whether you're shopping and want to know the final price after a coupon, calculating how much you'll save in a sale, or pricing products with a specific margin, the Cluster Tools Discount Calculator handles every variation.
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Calculation Modes
Sale Price (Original Price × % Off)
"$149.99 item, 35% off — what's the sale price?"
- Discount amount: 149.99 × 0.35 = $52.50
- Sale price: 149.99 - 52.50 = $97.50
What percentage is the discount?
"Original price $200, sale price $150 — what percentage off?"
- (200 - 150) ÷ 200 × 100 = 25% off
Original price from sale price and discount
"I see a price of $87 which is 30% off — what was the original price?"
- 87 ÷ (1 - 0.30) = $124.29
Stacking Discounts: How They Actually Work
Multiple discounts don't add — they compound. A 20% discount followed by an additional 10% discount is not 30% off. Here's the math:
$100 → -20% → $80 → -10% → $72
That's 28% total discount, not 30%. The second discount applies to the already-reduced price.
This is why retailers who advertise "20% off, then an extra 10% off" are offering less than "30% off" would imply — and why it's worth calculating exactly.
Sales Tax: Add After the Discount
In most jurisdictions, sales tax is calculated on the sale (discounted) price, not the original price. So:
$149.99 → 35% off → $97.50 → + 8.5% sales tax → $105.78 final price
The calculator lets you add a tax rate to see your final out-of-pocket cost.
Step-by-Step: How to Use
- Select your scenario — what you know and what you want to find.
- Enter the values — original price, discount percentage, or sale price.
- Optionally add a sales tax rate.
- Read the result — discount amount, sale price, and total with tax.
Frequently Asked Questions
How do I use a percentage-off coupon? Enter the original price and the coupon's percentage. The calculator shows you the exact discount amount and final price.
Does this work for Black Friday / Amazon sale calculations? Yes — it's particularly useful for quickly checking if a "sale" is actually a good deal vs. the typical selling price.
Can I calculate the original price if I only know the sale price and discount? Yes — use the "find original price" mode.
Related Tools
- Percentage Calculator — broader percentage calculations beyond discounts.
- Profit Margin Calculator — set selling prices based on cost and desired margin.
- ROI Calculator — calculate return on investment.
- [Tip Calculator — see the General tools section.