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DIY Cost Tools

DIY Cost Tools

Percent Off Calculator

Shopping Calculator

Percent Off Calculator

Calculate savings, sale subtotal, estimated tax, final total, and effective unit price for a percentage discount.

Calculate a discount

Savings$30.00
Sale subtotal$90.00
Estimated tax$5.40
Final total$95.40
Effective price each$95.40

Tax treatment, stacked promotions, shipping, fees, and coupon exclusions vary by seller and location.

How to use the percent off calculator

Enter the regular price of one item, the advertised percentage discount, and the quantity. Add the applicable sales-tax rate if you want an estimated checkout total. The calculator assumes tax is applied after the discount.

Discount formulas

Savings = original total x discount percentage / 100; sale subtotal = original total - savings

Estimated sales tax equals the discounted subtotal multiplied by the tax rate. Final total equals sale subtotal plus estimated tax. Effective price each divides the final total by quantity.

Worked example

One item regularly priced at $120 with a 25 percent discount saves $30 and has a $90 sale subtotal. At 6 percent sales tax, estimated tax is $5.40 and the final total is $95.40.

Accuracy and assumptions

  • The same discount applies to every unit.
  • Sales tax is calculated after the discount.
  • Shipping, deposits, recycling fees, and other charges are excluded.
  • Stacked coupons and tiered promotions must be calculated in their actual order.
  • Displayed currency is rounded to cents.

Frequently asked questions

Is 20 percent off followed by 10 percent off the same as 30 percent off?

No. Sequential discounts multiply. After 20 percent off, a second 10 percent discount applies to the reduced price, producing a combined 28 percent discount.

How do I calculate a coupon with a dollar amount?

Subtract the coupon amount from the appropriate subtotal first, then use this calculator for any percentage discount that applies afterward.

Why might the register total differ?

Retailers can apply discounts, tax, fees, and rounding in different orders. Product eligibility and local rules also vary.

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Sources and review

The calculator uses standard percentage arithmetic and shows the order of operations explicitly. It is a shopping estimate, not tax or financial advice. Calculator logic and examples were reviewed by the DIY Cost Tools editorial team on September 28, 2026.