Discount Calculator

1. Enter the original (list) price and the percent off.
2. Add a second discount if there is one — it is applied to the already-reduced price, not stacked onto the first.
3. Add your sales tax rate to see what you actually pay at the register.

Quick answers

How do I find the price before a discount?

Divide the sale price by (1 − discount). A $68 item after 15% off was $68 ÷ 0.85 = $80. Enter $80 here to confirm.

Is 20% off then 10% off the same as 30% off?

No. 20% then 10% leaves 0.80 × 0.90 = 72% of the price — a 28% total discount.

Edge cases and limits

• The calculator works forward from the original price; for “price before discount”, use the division above, then check it here.
• Coupons in dollars (for example $10 off) are not percentages — subtract them from the price first.

For one markdown, subtract the discount from 100% and multiply by the original price. Stacked discounts multiply rather than add because each new discount applies to the price left after the previous one.

To reverse a known discount, divide the sale price by the remaining-price decimal. For example, if $72 is the price after 20% off, the original price was $72 ÷ 0.80 = $90.

• Price after first discount = original × (1 − discount ÷ 100)
• Price after second discount = that price × (1 − second discount ÷ 100)
• You save = original price − final discounted price
• Effective discount % = saved ÷ original × 100
• Original price from a known sale price = sale price ÷ (1 − discount ÷ 100)
• Sales tax = discounted price × tax rate ÷ 100, added last

Sale price is what remains after each discount is applied in sequence. Amount saved is the difference from the original price, while effective discount expresses that total saving as one percentage for an honest comparison between offers.

Common mistakes and assumptions

• Adding two percentages together instead of applying them one after the other.
• Applying tax before the discount; here tax is calculated on the discounted price.
• Comparing an amount saved across different original prices instead of comparing the effective percentage.

A $240 item is 30% off, with an extra 15% coupon and 7% sales tax.

1. 1After 30% off: $240 × 0.70 = $168.
2. 2After the extra 15%: $168 × 0.85 = $142.80.
3. 3You save $240 − $142.80 = $97.20, an effective 40.5% discount — not 45%.
4. 4Sales tax = $142.80 × 0.07 = $10.00.
5. 5Total at the register = $152.80.

How do I calculate the sale price after a percentage discount?

Subtract the discount from 100%, convert that result to a decimal, and multiply by the original price. For 20% off, multiply by 0.80. A $65 item becomes $52.00, so the amount saved is $13.00.

Why isn't 30% plus 15% equal to 45% off?

The second discount is taken from the reduced price, not the original. Stacking 30% and 15% gives 40.5% off; the order of the two discounts does not change the result.

Is 25% off better than $25 off?

It depends on the price. They are identical at $100 — above that the percentage wins, below it the flat amount does. On an $80 item, 25% off saves $20 and the flat coupon saves $25.

Is sales tax charged before or after the discount?

Store discounts commonly reduce the taxable sale price, while rebates and local tax rules can be treated differently. This calculator applies the tax rate after the discounts; check your receipt or local rules when the distinction matters.

How do I convert "buy one get one half off"?

That is 25% off two items, since you pay 1.5 items for 2. Enter the two-item total and 25%.

How do I find the original price before a discount?

Divide the sale price by the percentage that remains. If an item costs $72 after 20% off, divide $72 by 0.80 to get the $90 original price. This calculator works forward from the original price; use that reverse formula when the sale price is the number you know.

How do I find the discount percentage from the original and sale prices?

Subtract the sale price from the original price, divide the savings by the original price, and multiply by 100. If a $100 item is marked down to $75, the discount is ($100 − $75) ÷ $100 × 100 = 25%.

Is the cheaper item always the better buy?

Not when the sizes differ. A discounted large pack can still cost more per ounce than a smaller one at full price, so check the winner with the Unit Price Comparison Calculator before you decide.

Worked answers with real figures and stated assumptions, written around the question people usually arrive with.

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