Discount Calculator

A discount calculator estimates a reduced selling price and the money saved compared with an original price. This tool supports percentage reductions, fixed amounts, reverse calculations, successive discounts, coupons, optional tax and quantities. Separate modes compare two offers or explore a discount’s effect on gross profit.

Use it for a shopping estimate or a retail pricing scenario. It does not verify a retailer’s advertised reference price, coupon eligibility or current offers. All monetary values use the selected currency; changing the currency changes formatting without exchanging money.

1. Start in Percentage Off Calculator, or select the calculation you need.
2. Enter the original unit price and discount. For a shopping quantity, enter the number of identical items.
3. For fixed reductions, remember that each amount applies once per order. In Multiple Discounts, add, remove or move steps to match your intended sequence.
4. Optionally enter coupons and their application order, then a sales tax rate if required.
5. Review the sale subtotal, savings, tax and final total. Expand the calculation steps, or copy, print or export the result.

Results update as you type. Reset calculator restores the 100-at-20%-off example and clears optional tax and coupons. Reverse and percentage-from-two-prices modes use the entered before-tax prices directly.

Discount amount = original price × discount percentage ÷ 100. Then use sale price = original price − discount amount.

At 25% off 200, multiply 200 × 25 ÷ 100 to get a reduction of 50. Subtracting 50 from 200 leaves a sale price of 150. At 0% off the price is unchanged; at 100% off it is zero before tax, provided a later fixed coupon does not exceed the remaining balance.

For a discount rate d written as a percentage, the unrounded discounted price is P × (1 − d/100). The retained share of the price is 100 − d percent. For 30% off, you retain 70%: an original price of 80 becomes 56 before tax.

For a completed price reduction, effective discount% = (original subtotal − discounted subtotal) ÷ original subtotal × 100. The calculator uses the actual cent-rounded subtotals for its effective percentage, which can differ slightly from a nominal rate on very small amounts.

Ten percent is one tenth. On a price of 50, the reduction is 5 and the sale price is 45. On 19.99, the exact reduction is 1.999; rounding that reduction to 2.00 leaves 17.99.

Twenty percent is one fifth. For an original price of 100, the reduction is 20 and the final sale price is 80. For three items priced at 50 each, the original order subtotal is 150; a 20% discount saves 30 and leaves 120 before tax.

Twenty-five percent is one quarter. On 200, the reduction is 50 and the remaining price is 150. The following examples assume a 100 original price and no tax or coupons.

Use original price = discounted price ÷ (1 − discount%/100). For 80 after a 20% reduction, divide by 0.8 to recover 100. Adding 20% to 80 would give 96 and does not reverse the original reduction.

Enter a sale price before tax and separate coupons. The recovered price is rounded to the nearest cent. Once a checkout has rounded amounts, several original prices can sometimes be consistent with a displayed sale price. At 100% off, a zero sale price cannot uniquely recover any original price; a positive sale price is inconsistent with that rate.

Use (original price − sale price) ÷ original price × 100. For a change from 120 to 90, the reduction is 30 and 30 ÷ 120 × 100 = 25%.

When the final price exceeds the original, the calculator identifies a price increase. For 100 to 120, that is a 20% increase and savings of −20. An original price of zero cannot produce a meaningful percentage change because the formula would divide by zero.

A percentage reduction scales with the current price; a fixed discount subtracts a specified monetary amount. On a 100 order, 20% saves 20, while a fixed 25 saves 25. On a 200 order, that same 20% saves 40 and exceeds the fixed 25.

Compare both on the same order basis. Each fixed discount in this tool applies once to the order subtotal, even when quantity exceeds one. An amount greater than the current balance is rejected rather than creating a negative price or silently being capped.

Apply each reduction to the remaining price. On 100, 20% off leaves 80, then 10% off saves 8 and leaves 72. Total savings are 28, equivalent to 28% off the original.

Ignoring money rounding, the retained price factor for two percentage discounts is (1 − d₁/100) × (1 − d₂/100). Adding discount rates would use the wrong base for later reductions.

Multiple Discounts supports percentage and fixed steps, editable names, and up/down controls. Order matters when types are mixed: 20% off then a fixed 10 leaves 70 from 100; a fixed 10 first leaves 90, then 20% off leaves 72. Cent rounding can also make reordered percentage steps differ slightly.

This tool’s convention is discounts first, then tax on the discounted subtotal. Tax = subtotal × entered tax rate ÷ 100; final total = subtotal + tax.

For an original price of 100 and 20% off, the subtotal is 80. With an illustrative user-entered 8% rate, tax is 6.40 and the final total is 86.40. The example is arithmetic, not a recommended or jurisdiction-specific rate.

Savings are shown before tax so the price reduction stays distinct from tax collected. Actual tax treatment can depend on location, product and promotion. Enter the applicable rate and confirm the seller’s taxable basis.

Coupons can reduce a sale price by a percentage or a fixed amount. In Sale Price & Coupons mode, select whether the coupon sequence runs before or after the sale discount. Each coupon appears once in the calculation breakdown.

On 100 with 20% off and a fixed 10 coupon applied afterward, the result is 70. Applying that coupon before the sale reduction instead gives 72. Add up to four coupon steps when the intended promotion permits stacking. The calculator does not establish a retailer’s eligibility rules, minimum spends or exclusions.

Use the same original price and quantity for both deals. On an original price of 100, Deal A at 20% off costs 80; Deal B with a fixed 25 reduction costs 75. Deal B costs 5 less before tax.

The comparison table shows each original subtotal, savings, effective rate, discounted subtotal, tax and final total. It identifies ties using the actual cent amounts. Different products, quantities, delivery costs or coupon eligibility can change the real purchase comparison and should not be treated as equivalent offers automatically.

Gross profit after discount is discounted pre-tax revenue − product cost. Gross margin divides that profit by discounted revenue; markup divides it by cost. On an original selling price of 100, cost of 60 and 20% off, revenue is 80, profit is 20, margin is 25% and markup is approximately 33.333333%.

The simplified direct-cost break-even discount is (original price − cost) ÷ original price × 100. At 100 and cost 60, that threshold is 40%. If the original price is already below cost, no nonnegative discount can bring it up to break-even. Zero revenue gives an undefined margin, and zero cost gives an undefined markup.

This analysis excludes overhead, fees and unentered expenses. Tax collected is not included as sales profit. For additional pricing calculations, use the Markup & Margin Calculator.

Money inputs use up to 2 decimal places. Each discount amount and tax is rounded to the nearest cent, halfway up. Discounts apply to the current order subtotal. Fixed discounts and coupons apply once per order, not per item. Savings exclude tax. Calculated percentages normally show up to 6 decimal places, extending to 12 for a very small nonzero value.

Monetary values are parsed directly into integer cents and calculated using BigInt. Percentage rates use exact decimal scaling rather than binary floating-point multiplication. For a half-cent reduction such as 50% of 0.01, the reduction rounds up to 0.01 and the remaining price becomes zero. A retailer that rounds a final unit price instead may produce a different result.

Each input and calculated order amount is limited to 1 trillion currency units. Quantity must be a whole number from 1 to 1,000,000. There are up to eight sale-discount steps and four coupon steps, with percentage and tax inputs from 0% to 100%. Money inputs with more than two decimal places are rejected rather than silently rounded.

Copy, print and CSV preserve cent amounts, step order, tax and assumptions. Reverse results are estimates rounded to cents; effective percentage displays are also rounded. Calculations run locally, without live offers, tax lookup or exchange-rate data.

Mathematical reference: OpenStax: percent, discount, markup and sales-tax arithmetic. Tax conventions here are illustrative calculation assumptions.