Discount Calculator
Enter the original price and a discount percentage below to instantly see the sale price, total savings, and effective discount — including a second stacked discount if you need it.
Price and discount
Result
How to calculate a discount
- Enter the original price before any discount.
- Enter the discount percentage — add a second stacked discount if the sale offers an extra percentage off.
- Read the final sale price, total savings, and effective combined discount instantly.
Use it as a quick sale price calculator for a single markdown, or as a percentage off calculator when you're stacking a coupon on top of an existing discount — either way the math updates as you type.
20% off + 20% off ≠ 40% off
When a second discount applies to an already-discounted price rather than the original price, the two percentages don't simply add together. A $100 item with 20% off drops to $80, and a further 20% off that $80 price takes off $16, not $20 — landing at $64. That's a 36% effective discount off the original price, not 40%, and this stacked discount calculator handles that math automatically.
FAQ
Is this discount calculator really free, with no sign-up?+
Yes. The tool runs entirely with JavaScript in your browser — there's no account, no API key, and no limit on how often you can use it.
How is the sale price calculated?+
The sale price is the original price minus the discount amount, where the discount amount equals the original price multiplied by the discount percentage.
How does a second stacked discount work?+
A second discount is applied to the already-discounted price, not the original price, which is how most "extra X% off" promotions actually work at checkout.
Why is 20% off then 20% off not the same as 40% off?+
Because the second 20% is calculated on the already-reduced price, not the original. Two stacked 20% discounts equal a 36% total discount, not 40%.
What does "effective discount" mean?+
It's the total percentage saved off the original price once both discounts are applied, expressed as a single combined percentage for easy comparison.
Tools for Dates & Calculations
How This Calculator Works
Your sale price and savings are calculated live with JavaScript, applying each discount in sequence to the running price — nothing you enter is uploaded to a server or stored anywhere.
Last updated: August 28, 2026.
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