Percent Off Calculator

How percent off is calculated

Percent off is a discount from a marked price. The sale price equals the original price multiplied by the share you still pay. If the discount is D percent, you pay (100 − D) percent of the original. In symbols: sale price = original × (1 − D / 100), and savings = original × (D / 100). A $80 jacket at 25% off is $80 × 0.75 = $60, so you save $20.

The quick mental versions are worth memorizing because sale signs are written to be skimmed. Ten percent off means you pay 90%. Twenty-five percent off means you pay 75%. Fifty percent off means you pay half. Seventy-five percent off means you pay a quarter. A "third off" is about 33%, so you pay about 67% of the tag.

This calculator takes one original price and one discount percent. It reports the sale price, the dollars saved, and the amount you pay. It does not add sales tax, shipping, or a second coupon. The pay line matches the sale price because both are the discounted merchandise total before those extras.

Worked examples

Example 1: A straightforward 25% off

Original $80, discount 25%. Savings = 80 × 0.25 = $20. Sale price = $60. You pay three-quarters of the tag. The same pattern scales: $40 at 25% off is $30, and $120 at 25% off is $90.

Example 2: Forty percent off a larger tag

Original $200, discount 40%. Savings = $80. Sale price = $120. You pay 60% of the original. If a competing store lists the same item at $125 with no discount, the $120 sale is the better merchandise price. Compare the final shelf price, not the size of the percent badge.

Example 3: Two discounts in a row

A sign says 20% off, and the register takes an extra 10% off the sale price. Start with $100. After 20% off, the price is $80. Ten percent of $80 is $8, so the second discount leaves $72. The combined discount is $28, which is 28% off the original, not 30%. Percents of different bases do not add. Run the calculator twice: once for the first markdown, then again using the sale price as the new original.

Example 4: Cents, tax, and the amount you actually tender

A $49.99 item at 30% off saves $14.997, so the merchandise total is $34.993, which a register typically settles to $34.99. Sales tax is usually charged on that discounted price. At 8% tax, $34.99 × 1.08 is about $37.79 out the door. This page's dollar readout rounds to the nearest dollar, which is fine for a quick comparison and too coarse for a receipt. When cents matter, apply the formula and then add tax the way the receipt will.

Example 5: "Buy one, get one half off"

Two items at $40 each: you pay $40 for the first and $20 for the second, $60 total instead of $80. That is $20 saved on $80, or 25% off the pair, not 50% off the trip. "Buy two, get one free" on three equal prices means you pay for two of the three, which is one-third off the group. Equal prices are the assumption. If the free or discounted item must be the cheaper one, use that lower price in the savings step.

When to use this

Use it when a tag, email, or coupon states a percent off a known price and you want the dollars before you commit. Typical moments: a clothing markdown, a "extra 15% off sale items" code, a classroom percent problem, and a check that a contractor's "10% off labor" line matches the quote. It is also the right tool when you are deciding whether a percent-off offer beats a flat dollar coupon. A $15 coupon on a $40 item is deeper than 25% off ($10). A $15 coupon on a $200 item is shallower than 10% off ($20).

Percent off is not the same job as percent change. Percent off starts from a marked price and only goes down. Percent change compares any two numbers and can be an increase. If you already know the old price and the new price and want the percent, use the Percent Change Calculator. If you are comparing package sizes after the discount, follow up with the Unit Price Calculator so a "40% off" family box is judged per ounce or per count.

Common mistakes

• Adding stacked percents. 20% then 10% is 28% off the original in the example above, not 30%.
• Reading "up to 70% off" as the price of the item in your hand. The ceiling applies to selected styles. The item you want may be 15% off.
• Treating BOGO language as a discount on every unit. Half off the second item is 25% off two equal items.
• Comparing percents while the original prices differ. Forty percent off an inflated compare-at price can cost more than 10% off a realistic price.
• Forgetting tax, shipping, and minimums. A code that needs $75 in the cart does nothing at $60, and shipping can erase a small percent.
• Applying the percent to the tax as well as the goods. Compute the merchandise discount first, then tax the sale price unless the receipt clearly does something else.

Limitations

One price and one percent at a time. No tax table, no shipping, no "spend $50, save $10" threshold, and no store price-match policy. Dollar amounts on the result panel are rounded to the nearest dollar, so a price that needs cents should be finished with the formula. Discounts outside 0 to 100 still produce a number, and the page warns you; a negative discount or a percent over 100 is almost always a typo. The tool does not know whether a manufacturer coupon applies to the original price or the sale price. Read that line on the coupon and choose the base accordingly.

FAQ

Is 20% off the same as paying 80%?

Yes. The discount and the portion you pay always add to 100% of the original price. Twenty percent off leaves 80% to pay.

How do I find the percent if I know both prices?

Subtract the sale price from the original, divide by the original, and multiply by 100. A drop from $50 to $35 is $15 / $50 = 0.30, or 30% off. That is percent-change math with a decrease.

Does the register take the discount before tax?

In ordinary US retail, sales tax is charged on the price after the merchandise discount. Confirm on the receipt if a fee or a special tax rule is involved. Add the tax yourself after you have the sale price.

What is the effective discount on "buy two, get one free"?

If all three items cost the same, you pay two-thirds of the full price, which is 33.3% off the group. If the free item has to be the lowest price, compute savings from that lowest price only.

Why does 50% off and then 50% off not mean the item is free?

The second 50% applies to the already reduced price. $100 becomes $50, then $25. You still pay a quarter of the original. Each cut is half of whatever is left, not half of the starting price again.

Practical tips

Rewrite the sign as the percent you pay before you compare stores. "30% off" becomes "pay 70%." For a stacked offer, write the intermediate price down and run the second percent on that number only. Keep the original compare-at price in the notes so a later "extra" code is not accidentally applied to the wrong base.

When two deals look close, include tax and shipping in a one-line total. A 20% discount that still charges $8 shipping can lose to a smaller percent with free shipping. For groceries and warehouse clubs, convert the sale price to a unit price so a large package on sale is compared fairly with a smaller regular-priced package.

In a classroom setting, estimate first: 10% by moving the decimal, then adjust. Twenty-five percent is a quarter of the price, so divide by four to get the savings. The calculator is there to confirm the estimate, which is how you catch a misplaced decimal.

Related calculators

• Percent Change Calculator for the percent between any two numbers
• Fraction, Decimal, and Percent Converter
• Tip Calculator for a percent added on, rather than taken off
• Unit Price Calculator
• Ratio Calculator
• GPA Calculator