# Discount Calculator

> Sale price = original price × (1 − discount ÷ 100), so 25% off $120 takes off $30 and you pay $90; an extra 10% off that brings it to $81, a 32.5% total discount. The calculator can also add sales tax or work back from a sale price to the original price.

- Interactive calculator: https://calculatorswithsteps.com/discount-calculator
- Category: Everyday & Conversion Calculators
- Last updated: 2026-11-10
- Publisher: Calculators With Steps (calculatorswithsteps.com)

## How to use the discount calculator

Choose what you want to find from the drop-down:

| You know | Choose | Example |
| --- | --- | --- |
| The price and the % off | Sale price after a % discount | $120 at 25% off = $90 |
| The price and a fixed amount off | Sale price after an amount off | ₹2,499 with ₹500 off = ₹1,999 |
| The sale price and the % off | Original price from the sale price | $90 after 25% off = $120 |
| The original and sale prices | Discount % from original and sale price | $80 → $60 = 25% off |

For the first two options you can also enter an **extra discount** (a coupon or member discount taken off the reduced price) and a **sales tax** rate. The currency menu switches between dollars, rupees, euros, pounds and more.

## Discount formulas

**Amount off = original price × discount % ÷ 100**

**Sale price = original price × (1 − discount % ÷ 100)**

**Discount % = (original price − sale price) ÷ original price × 100**

**Original price = sale price ÷ (1 − discount % ÷ 100)**

With a stacked discount, multiply the factors together: **sale price = original × (1 − d₁) × (1 − d₂)**, where d₁ and d₂ are the two discounts as decimals. Sales tax, if any, is added last: **final price = sale price × (1 + tax rate)**.

## Worked example: stacked discount with sales tax

A jacket is marked **$120**. It is 25% off, you have a coupon for an extra 10% off, and sales tax is 8%.

| Step | Working | Result |
| --- | --- | --- |
| First discount | 120 × (1 − 0.25) | $90.00 |
| Extra 10% off | 90 × (1 − 0.10) | $81.00 |
| Total saved | 120 − 81 | $39.00 |
| Effective discount | 39 ÷ 120 × 100 | 32.5% |
| Sales tax | 81 × 0.08 | $6.48 |
| You pay | 81 + 6.48 | $87.48 |

The two discounts add up to 35% on paper, but the real saving is 32.5%, because the 10% coupon is taken from $90 rather than $120.

## Common discount mistakes

- **Adding stacked discounts.** "30% off, then an extra 20% off" is 44% off in total, not 50%. The order does not matter: 20% then 30% also gives 44%.
- **Reversing a discount by adding the percentage back.** If something costs $90 after 25% off, the original was $120, not $112.50. Divide by 0.75 instead of multiplying by 1.25.
- **Comparing "% off" with "amount off" by eye.** $20 off a $120 item is 16.7% off, which is less than a 25% discount. Use the discount % option to compare offers on equal terms.
- **Forgetting tax.** A $90 sale price in a state with 8% tax costs $97.20 at the register. Use the [sales tax calculator](https://calculatorswithsteps.com/sales-tax-calculator) for tax on its own.

## Discounts in India: MRP, flat offers and GST

In India the maximum retail price (MRP) printed on a product already includes GST, so the discounted price is what you pay. For example, 40% off an MRP of **₹1,999** brings it to **₹1,199.40**, a saving of ₹799.60. A "flat ₹500 off" on ₹2,499 brings the price to ₹1,999, which is a discount of 20.01%. That is useful when comparing a flat offer with a percentage offer on the same item.

For business invoices where GST is charged on top of a discounted value, apply the discount first and then the GST rate. The [GST calculator](https://calculatorswithsteps.com/gst-calculator) adds or removes GST at 5%, 18% and the other slabs.

## Which is better: a percentage off or a fixed amount off?

A percentage discount grows with the price, while a fixed amount stays the same, so the better deal depends on what you buy. Compare "25% off" with "$25 off":

| Price | 25% off saves | $25 off saves | Better deal |
| --- | --- | --- | --- |
| $80 | $20.00 | $25.00 | $25 off |
| $100 | $25.00 | $25.00 | Same |
| $150 | $37.50 | $25.00 | 25% off |

The break-even price is the fixed amount divided by the percentage as a decimal: $25 ÷ 0.25 = $100. Above that price the percentage wins. Stores often let you use only one of the two, so run both through the calculator before you check out.

## Quick discount tricks

- 10% off: move the decimal point one place left and subtract. 10% off $64 is $64 − $6.40 = $57.60.
- 25% off: divide by 4 and subtract, or multiply by 0.75.
- "Buy one, get one 50% off" on two items of the same price works out to 25% off both.
- To check a deal against a price you know, find the percentage between the two with the [percentage calculator](https://calculatorswithsteps.com/percentage-calculator).

## Frequently asked questions

### How do I calculate a discount?

Multiply the original price by the discount percentage and divide by 100 to get the amount off, then subtract it. For 25% off $120, the discount is $30 and the sale price is $90.

### How do I calculate the discount percentage from two prices?

Subtract the sale price from the original price, divide by the original price and multiply by 100. A price cut from $80 to $60 is (80 − 60) ÷ 80 × 100 = 25% off.

### Is 30% off plus an extra 20% off the same as 50% off?

No. The second discount applies to the already reduced price, so you pay 0.70 × 0.80 = 0.56 of the original, which is 44% off. On a $100 item you save $44, not $50.

### How do I find the original price from a sale price?

Divide the sale price by (1 − discount ÷ 100). If an item costs $90 after 25% off, the original price was 90 ÷ 0.75 = $120. Adding 25% to $90 gives $112.50, which is wrong.

### Is sales tax charged before or after the discount?

In most U.S. states, sales tax is charged on the discounted price for store discounts. With 25% and an extra 10% off a $120 item and 8% sales tax, you pay $81 plus $6.48 tax, or $87.48. Some states tax the full price when a manufacturer's coupon is used.

### How do I calculate a discount in rupees on MRP?

Multiply the MRP by (1 − discount ÷ 100). 40% off an MRP of ₹1,999 gives ₹1,199.40, a saving of ₹799.60. MRP in India already includes GST, so there is no tax to add.

### What is the discount formula in Excel?

With the original price in A2 and the discount percentage in B2 (entered as 25%), the sale price is =A2*(1-B2). With the original price in A2 and the sale price in B2, the discount percentage is =(A2-B2)/A2, formatted as a percentage.

## Sources

- [Wikipedia – Percentage](https://en.wikipedia.org/wiki/Percentage)
- [Wikipedia – Discounts and allowances](https://en.wikipedia.org/wiki/Discounts_and_allowances)