Monster Discount Calculator
Find the sale price, your total savings, and the final cost with tax — before you reach the register.
| You save | $0 |
| Discount amount | $0 |
| Price with tax | $0 |
How it works
The discount is price × discount %, subtracted from the original price to get the sale price. Sales tax is then applied to the discounted price — which is why sale items cost less tax too.
Formula & worked example
Formula: Sale price = original price × (1 − discount %). Sales tax is then charged on the discounted price, not the original.
Worked example: An $80 item at 25% off sells for $60.00; with 8% sales tax the total at the till is $64.80.
When to use this
- A sale sign says a percentage off and you want the actual price before you queue, not after.
- You are comparing two stores offering different percentages off different starting prices.
- A coupon is in hand and you want the till total, sales tax included, before deciding if the trip is worth it.
- You run a small shop and are testing what a planned promotion does to the price a customer actually pays.
How to use it, step by step
- Enter the original price exactly as tagged.
- Enter the discount percentage from the sign or coupon.
- Add your local sales tax rate if you want the final till total; leave it at zero for the bare sale price.
- Read the sale price, the amount saved, and the price with tax as three separate lines — they answer three different questions.
- For a second coupon applied after the first, run the sale price through again; sequential discounts multiply rather than add.
What the inputs mean
| Input | What it is | Typical values |
|---|---|---|
| Original price | The full tagged price before any discount | Any amount, cents included |
| Discount percent | The percentage taken off the original price | Everyday sales 10–30%; clearance 50–70% |
| Sales tax percent | Optional local rate, applied to the discounted price | Combined rates commonly 6–10%; zero if you only want the sale price |
Another worked example
A jacket tagged at $149.99 with 30% off and 6.5% sales tax: the discount takes $45.00 off, the sale price is $104.99, and tax on that discounted price brings the till total to $111.82. Note the tax was charged on $104.99, not on $149.99 — the discount quietly saved a few dollars of tax as well as the $45 on the jacket.
Frequently asked questions
How do stores compute a discount?
The same way this calculator does: take the percent off the sticker price. A 25% discount on $120 is $30 off, so you pay $90. "Percent off" always refers to the original price, not the sale price.
Can I stack two discounts, like 20% + 10%?
Usually they're applied one after another, not added. 20% then 10% on $100 = $80, then $72 — a 28% total discount, not 30%. Enter the final effective percent above, or run it twice.
What's the difference between discount and sale price?
The discount is the amount taken off (your savings); the sale price is what you actually pay. This calculator shows both so there's no confusion.
Why is my register total higher than the sale price this shows?
Usually something this tool does not model: a manufacturer coupon is sometimes taxed on the pre-discount price in some states, and deposits, bag fees, delivery or a discounted extended warranty can be added after the item price. If the gap is more than a few cents of rounding, ask which line was added — the discount math itself is the part you can verify here.
How do I work out the original price if I only know the sale price and the percent off?
Divide the sale price by what remains after the discount. A $104.99 price after 30% off divides by 0.70 to give about $149.99. Dividing by the discount percent itself is the common mistake — the sale price is the percentage that is left, not the percentage that was removed.
What does 'up to 70% off' actually mean?
That the single deepest discount in the store reaches 70%, while most items carry smaller markdowns. Judge any individual item by running its own tag price and its own percentage through this calculator rather than the headline number on the banner.