What this calculator does
Calculate the pre-tax price and tax amount when the total price including sales tax is known.
How it works
The calculator evaluates pre-tax price = total ÷ (1 + tax rate); tax = total − pre-tax price. Inputs are checked before calculation, and invalid values such as zero denominators or out-of-range selections produce a clear error instead of a misleading result.
Input query strings and outputs
Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.
Input query strings
2-
?totalWithTax=Total price including taxMoney · Required · Default: 106.25
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?salesTaxRate=Sales tax ratePercentage · Required · Default: 6.25
Outputs
4-
preTaxPricePrice before taxCurrency · Primary output
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salesTaxAmountSales tax amountCurrency
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taxShareOfTotalTax as % of totalPercentage
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verificationTotalRecomputed totalCurrency
Inputs and results
The inputs are Total price including tax, Sales tax rate. Results include Price before tax, Sales tax amount, Tax as % of total, Recomputed total.