Discount and tax guide: calculate the final shopping price

When this tool helps

A sale label does not always tell you the amount due at checkout. This tool separates the original price, discount saving and tax so you can see how the final total was formed. Tax is applied after the discount in this model.

Enter a price and discount percentage in the empty fields. Add a tax rate only if it applies to your calculation; a blank tax field means zero. The app uses the rate you supply and does not decide which local tax rules govern a purchase.

What to enter

These are the candidate Android fields, not a form on this website. Editable fields in the app start empty; modes and units are selected separately.

Original price: The price before the discount, in your selected currency label.
Discount (%): A percentage from 0 to 100.
Tax after discount (%): Optional; blank means no tax in this calculation.

Worked example · not prefilled app data

Try this example after the update is available

The values below explain the calculation. They are not a quote, a live measurement or an automatic answer for your situation.

Original price: 100
Discount (%): 20
Tax after discount (%): 10

Checked example result88.00

A 20% discount saves 20.00 from 100.00. The discounted price is 80.00; tax at 10% adds 8.00, giving 88.00.

Formula and assumptions

Final price = original price × (1 − discount ÷ 100) × (1 + tax ÷ 100)

All amounts use the same currency; choosing a label does not convert money.
This model excludes shipping, fixed coupons, minimum spends and retailer-specific rounding rules.

A common mistake to avoid

Do not add the discount rate and tax rate together. They act on different amounts in this calculation. A shop may use a different legal or promotional ordering, which you should check separately.

Find this tool in the Android update

When you have the redesigned Android update, open Tools and search for Discount & tax, or find it under Shopping.
Open the tool, choose the mode or units relevant to your task, then enter your own values.
Review the result and explanation. Use Calculate & save only if you want the calculation kept in local History; Copy result does not send it to our server.

This guide is an educational preview of the update in testing, not an announcement that Google Play has approved or published it. Calculations are in the native app; no web calculator or download is offered on this page.

Questions about Discount & tax

Can I leave the tax field empty?

Yes. A blank optional tax field is treated as zero; the price and discount still need valid input.

Can I enter a discount above 100%?

No. The candidate accepts discount percentages from 0 to 100 and rejects negative prices.