Discount Calculator
Enter any two values. We calculate the third — plus tax.
A discount calculator takes the guesswork out of markdowns, coupon codes, and clearance sales. Whether you’re comparing a 20% off tag at checkout or trying to work out how much a $150 jacket actually costs after a 30% discount and 8% sales tax, doing the math by hand is slow and easy to get wrong. This free online discount calculator solves it instantly — type in any two values (the original price, the discount, or the final sale price) and it fills in the third, live, as you type. It works as a percentage discount calculator or a flat-dollar discount calculator, and it can layer sales tax on top so you see the real total before you reach the register.
How to Calculate a Percentage Discount
The formula behind every percent discount calculator is simple: multiply the original price by the discount percentage, then subtract that amount from the price.
Discount amount = Original price × (Discount % ÷ 100)
Sale price = Original price − Discount amount
For example, an $80 pair of shoes with a 25% discount comes out to $80 × 0.25 = $20 off, for a final Price after Discount of $60. Enter the price and the percentage into the calculator above and it runs this same formula automatically, rounding to the cent so the numbers match what you’ll actually see on a receipt.
Discount Calculator With Tax
Most in-store and online purchases add sales tax after the discount is applied, not before — so a plain percentage discount calculator alone won’t show your real total. This tool doubles as a sales tax and discount calculator: once a price after discount is set, add your local tax rate in the optional Sales Tax field and it shows the tax amount and final total together. That’s useful for budgeting a big purchase, checking a receipt, or figuring out whether a “30% off” sale is still a good deal once tax and discount are combined.
Work Backward: Find the Original Price or Discount Rate
Sometimes you know the sale price but not the original — or you want to check whether a store’s advertised discount is accurate. Because this price discount calculator solves for whichever field you leave blank, you can:
- Enter the original price and the discount to find the sale price.
- Enter the original price and the sale price to find the discount percentage or dollar amount.
- Enter the discount and the sale price to work out what the item cost before the discount.
This flexibility makes it useful as an online discount rate calculator for shoppers, and as a discount calculator in percentage or dollar terms for retailers pricing a sale.
Quick Discount Reference
Need a fast estimate without typing into the calculator? Here’s what a few common discount rates take off a round price:
- 10% off $100 = $10 off → $90
- 20% off $50 = $10 off → $40
- 25% off $80 = $20 off → $60
- 30% off $150 = $45 off → $105
- 50% off $60 = $30 off → $30
These are rounded examples — for exact figures, especially once sales tax is added on top, use the discount calculator above.
Why Use an Online Discount Calculator
There are plenty of ways to work out a discount rate by hand, but a free online discount calculator is faster and removes the risk of arithmetic mistakes on a big purchase:
- Fast and accurate — no manual percentage math, no rounding errors.
- Works both ways — solve for the discount, the sale price, or the original price.
- Handles sales tax and discount together, so you see the true final total.
- Free, with no sign-up and nothing saved on our servers.
- Built to work on any device, including at checkout on mobile.
Frequently Asked Questions
What is a discount calculator?
A discount calculator is a tool that works out the relationship between an item’s original price, a discount (as a percentage or a dollar amount), and the final sale price — enter any two of the three values and it solves for the third instantly.
What is a discount percentage calculator?
A discount percentage calculator — also called a percent discount calculator or percentage off calculator — is a tool that tells you what percentage an item has been marked down, or how much a given percentage takes off the price. This tool covers both directions of that math in one place.
Is this online discount calculator free to use?
Yes — it’s a completely free online discount calculator with no sign-up or account required. It runs entirely in your browser and doesn’t store your numbers anywhere.
Does this discount calculator include sales tax?
Yes. Add your local sales tax rate in the optional Sales Tax field to see the tax amount and the total price after discount, so it also works as a combined tax and discount calculator.
Can I enter the discount as a dollar amount instead of a percentage?
Yes. Use the % / $ toggle above the Discount field to switch between a percent discount calculator and a flat dollar amount, whichever you know.
How do I calculate a discount percentage manually?
Divide the discount amount by the original price, then multiply by 100. For example, $20 off an $80 item is (20 ÷ 80) × 100 = 25% off. Our percentage discount calculator runs this formula for you automatically.
How is a 20% discount calculated?
Multiply the original price by 20% (0.20), then subtract that amount from the price. On a $50 item, 20% off is $50 × 0.20 = $10, so the sale price — taking 20% off — is $50 − $10 = $40. Enter your own price above and set the discount to 20% to see it calculated instantly, tax included if you need it.
How can I calculate a 10% discount?
A 10% discount is easy to estimate by hand: move the decimal point on the price one place to the left. On a $45 item, 10% is $4.50, so the sale price is $45 − $4.50 = $40.50. For any other percentage, or to double-check your mental math, enter it into the calculator above.
What is a discount factor, and how do I calculate it?
The discount factor is what’s left of the price after the discount, expressed as a decimal — for a 25% discount, the factor is 1 − 0.25 = 0.75. Multiply the original price by the discount factor to get the sale price in one step, e.g. $80 × 0.75 = $60.
How do I calculate a discount using a calculator?
On a plain calculator, multiply the original price by the discount rate — type the price, ×, then the discount number followed by the % key — to get the discount amount, then subtract that from the price for the sale price. No % key? Multiply by the decimal form instead (20% = 0.20). This calculator does both steps for you automatically once you enter the price and discount.
How do I find the discount percentage on a calculator?
Subtract the sale price from the original price to get the discount amount, divide that by the original price, then multiply by 100. For example, a $100 item marked down to $75 is (100 − 75) ÷ 100 × 100 = 25% off. Enter the original price and the Price after Discount above and the percentage fills in automatically.
Can I calculate the original price from a sale price and discount?
Yes. Enter the discount percentage or amount and the Price after Discount, and the calculator solves for the original price automatically — handy for checking whether an advertised discount rate is accurate. Manually, divide the sale price by the discount factor: a $60 sale price after a 25% discount is $60 ÷ 0.75 = $80.