Discount Calculator

How to use the Discount Calculator

Calculate savings and sale price from a custom or preset discount, then optionally estimate tax applied to the discounted subtotal.

Calculate the sale price, amount saved, and optional post-discount tax from an original price and discount rate. The steps are shown separately so percentages are not applied in the wrong order.

Fieldlet calculates locally and shows a practical estimate. Confirm consequential financial, contractual, health, or compliance decisions with an authoritative source.

1. Enter the original price and choose a preset or custom percentage discount.
2. Enter an optional post-discount tax rate, or leave it at zero.
3. Fieldlet shows savings, sale price, tax, and the final total as separate steps.

Last reviewed for accuracy: 2026-09-01

Worked examples

How the result is produced

Fieldlet converts rates to decimals, subtracts the discount from the original price, and applies any entered tax to the discounted subtotal. Currency rounding is displayed to practical decimal places.

• Savings = original price × discount rate
• Sale price = original price − savings
• Post-discount tax = sale price × tax rate

Keep each checkout step visible

The preset buttons change only the discount rate. Optional tax is then calculated on the discounted subtotal, letting you compare original price, savings, sale price, tax, and final total without combining the percentages incorrectly.

• Confirm whether the listed price already includes tax.
• Enter zero tax when it should not be estimated.
• Compare the result with retailer fees and coupon rules.

Limitations and common mistakes

• Retailers may apply coupons, taxes, fees, and rounding in a different sequence.
• The calculator does not determine whether an advertised discount or tax treatment is legally correct.

Common questions