# Discount Calculator

> Free discount calculator: enter the original price and discount percentage to instantly see the sale price and how much money you save.

Seeing 30% off and wondering what you actually pay? Enter the original price and the discount to get the sale price and your savings instantly.

*Interactive tool: enter your values at https://toollantern.win/discount-calculator/ and results update instantly in your browser.*

## What this calculator does

This discount calculator takes an original price and a discount percentage and instantly returns the two numbers shoppers care about: the sale price you will pay and the amount of money you save. It runs entirely in your browser, so it works in the store aisle too.

## How the math works

- **Amount saved** = original price × (discount ÷ 100)

- **Sale price** = original price − amount saved

## Worked example

A jacket costs **$120** and is **30% off**. You save 120 × 0.30 = **$36**, and the sale price is 120 − 36 = **$84**. You pay 70% of the original price.

## Stacked discounts are not additive

A common trap: "20% off, plus an extra 10% off at checkout" is not 30% off. The second discount applies to the already reduced price: 0.80 × 0.90 = 0.72, so you pay 72% and the real discount is 28%. To find the original price from a sale price, divide: original = sale ÷ (1 − discount).

## Limitations

The calculator applies one flat percentage discount and does not model sales tax (added at checkout in the US), shipping, or tiered promotions like "buy one, get one half off". Always check the final checkout total before paying.

## Frequently asked questions
### How do you calculate a discount percentage?

Multiply the original price by the discount as a decimal. For 25% off $80: 80 × 0.25 = $20 saved, so the sale price is $60. This calculator does it for you instantly.

### How much is 20% off $100?

$20 off, so the sale price is $80. In general, 20% off means you pay 80% of the original price: just move the decimal and multiply.

### What is the difference between the discount and the sale price?

The discount is the amount taken off (what you save). The sale price is what you actually pay after the discount is subtracted. Discount + sale price always equals the original price.

### Can you add two discounts together, like 20% then 10%?

No, they multiply rather than add. A 20% discount followed by 10% off the reduced price equals 1 − (0.80 × 0.90) = 28% off total, not 30%.

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

Divide the sale price by (1 − discount as a decimal). If something costs $70 after 30% off, the original was 70 ÷ 0.70 = $100.

### Does the calculator include sales tax?

No. It shows the pre-tax sale price. In the US, sales tax is added at checkout, so your final total will be a little higher.

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Interactive version: https://toollantern.win/discount-calculator/