# Discount Calculator

Calculate sale prices and savings instantly. Enter original price and discount to see final price, savings, and effective discount.

## What this calculates

Find out exactly how much you save with our free discount calculator. Enter the original price and discount percentage to instantly see the sale price, total savings, and effective discount. Supports stacked discounts (e.g. 25% off plus an extra 10% off) and optional sales tax calculation.

## Inputs

- **Original Price** ($) — min 0 — The item's price before any discount.
- **Discount Percentage** (%) — min 0, max 100 — The discount percentage off the original price.
- **Additional Discount (%)** (%) — min 0, max 100 — Optional second discount applied after the first (e.g. extra 10% off sale price).
- **Sales Tax Rate** (%) — min 0, max 30 — Optional sales tax applied to the discounted price.

## Outputs

- **Final Price** — formatted as currency — The price after all discounts (before tax).
- **You Save** — formatted as currency — Total amount saved from the original price.
- **Effective Discount** — formatted as percentage — The total effective discount percentage (accounts for stacked discounts).
- **Price After Tax** — formatted as currency — Final price including sales tax.
- **Tax Amount** — formatted as currency — Sales tax on the discounted price.

## Details

Here's how it works: Final Price = Original Price x (1 - Discount / 100). For example, a $120 item at 25% off costs $120 x 0.75 = $90, saving you $30.

Stacked discounts are a common retail strategy where an additional percentage is taken off an already-discounted price. Important: stacked discounts are NOT additive. A 25% discount plus a 10% discount is NOT 35% off. Instead, the second discount applies to the already-reduced price. On a $120 item: first 25% off gives $90, then 10% off $90 gives $81. The effective discount is 32.5%, not 35%.

The general formula for stacked discounts is: Effective Discount = 1 - (1 - d1/100) x (1 - d2/100), where d1 and d2 are the discount percentages. The order of the discounts does not matter mathematically -- 25% then 10% gives the same result as 10% then 25%.

When sales tax applies, it is calculated on the discounted price, not the original price. This means discounts also reduce the tax you pay. A $120 item at 25% off with 8% tax: discounted price is $90, tax is $7.20, final price is $97.20. Without the discount, you would pay $129.60 (including tax), so the total savings is $32.40.

## Frequently Asked Questions

**Q: How do I calculate the sale price after a discount?**

A: Multiply the original price by (1 - discount percentage / 100). For example, $80 at 30% off: $80 x (1 - 0.30) = $80 x 0.70 = $56. Alternatively, calculate the discount amount ($80 x 0.30 = $24) and subtract from the original ($80 - $24 = $56).

**Q: How do stacked discounts work?**

A: Stacked discounts apply sequentially, not additively. The second discount is applied to the already-discounted price. For example, 20% off plus 15% off does NOT equal 35% off. On a $100 item: 20% off = $80, then 15% off $80 = $68. The effective discount is 32%, not 35%. The formula is: Effective Discount = 1 - (1 - d1/100) x (1 - d2/100).

**Q: Is sales tax calculated on the original or discounted price?**

A: Sales tax is calculated on the discounted (final sale) price, not the original price. This means a discount also reduces the amount of tax you pay. For example, a $100 item at 20% off with 8% tax: the discounted price is $80, and the tax is $6.40 (8% of $80), for a total of $86.40.

**Q: How do I calculate what percentage off something is?**

A: To find the discount percentage: Discount % = (Original Price - Sale Price) / Original Price x 100. For example, an item originally $80 now selling for $52: ($80 - $52) / $80 x 100 = 35% off.

**Q: Does the order of stacked discounts matter?**

A: No, the order does not affect the final price. A 25% discount then 10% gives the same result as 10% then 25%. This is because multiplication is commutative: Price x 0.75 x 0.90 = Price x 0.90 x 0.75. The final effective discount is the same regardless of the order applied.

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Source: https://vastcalc.com/calculators/finance/discount
Category: Finance
Last updated: 2026-04-21