Know the total you paid but not the price before tax? Enter the tax-inclusive total and the sales tax rate to get the pre-tax price and the tax amount. Paste a list of receipts in batch mode to split many totals at once and download the results.
Last updated:
Mode
$
%
%
Enter your values to see the result.
Advertisement
Advertisement
How to use the Reverse Sales Tax Calculator
Choose single total or batch mode.
Enter the total including tax, or paste a list of totals, one per line (a label before the amount is optional).
Enter the sales tax rate, plus any local rate that applies on top of the state rate.
Read the price before tax and the tax amount.
Copy the results or download the batch table as CSV for your bookkeeping.
Reverse sales tax formula
Sales tax is added on top of the price, so the total is price × (1 + rate). To go backwards, divide:
Pre-tax price = Total ÷ (1 + rate) and Tax = Total − Pre-tax price
The rate is written as a decimal (8.25% = 0.0825). Example: a $54.12 receipt at 8.25% tax: $54.12 ÷ 1.0825 = $49.995, about $50.00 before tax, so the tax was about $4.12. A $108.25 total works out exactly: $100.00 plus $8.25 tax.
A quick shortcut for the tax alone: Tax = Total × rate ÷ (1 + rate). At 8.25% that is 7.62% of the total, not 8.25%.
Reverse sales tax reference table
The divisor to use for common rates, the share of a tax-inclusive total that is tax, and the split of a $100.00 total.
Tax rate
Divide total by
Tax as % of total
Pre-tax part of $100
Tax part of $100
2.9%
1.029
2.8183%
$97.18
$2.82
4%
1.04
3.8462%
$96.15
$3.85
5%
1.05
4.7619%
$95.24
$4.76
6%
1.06
5.6604%
$94.34
$5.66
6.25%
1.0625
5.8824%
$94.12
$5.88
7%
1.07
6.5421%
$93.46
$6.54
7.25%
1.0725
6.7599%
$93.24
$6.76
8%
1.08
7.4074%
$92.59
$7.41
8.25%
1.0825
7.6212%
$92.38
$7.62
8.875%
1.0888
8.1515%
$91.85
$8.15
9.5%
1.095
8.6758%
$91.32
$8.68
10%
1.1
9.0909%
$90.91
$9.09
Frequently asked questions
How do you calculate the price before tax?
Divide the total by 1 plus the tax rate as a decimal: pre-tax price = total ÷ (1 + rate). For a $108.25 total at 8.25% tax, $108.25 ÷ 1.0825 = $100.00, so the tax was $8.25.
Why can't I just subtract the tax rate from the total?
Because sales tax is a percentage of the pre-tax price, not of the total. Taking 8.25% off $108.25 gives $99.32, which is wrong. The tax is a smaller share of the total: rate ÷ (1 + rate), or about 7.62% at an 8.25% rate.
How do I handle state plus local sales tax?
Add the rates together and use the combined rate. For example a 6.25% state rate plus a 2% local rate is 8.25% in total. The calculator has a separate field for the local rate and adds them for you.
Why is my result one cent off the receipt?
Stores round tax to the cent, and some round each item separately. Because of that, some totals cannot be produced exactly from a whole-cent price. The calculator shows a rounding check whenever the pre-tax price times the rate does not give back the exact total.
Does this work for VAT or GST?
Yes, the math is the same for any tax added on top of a price. For VAT-specific options such as adding and removing VAT at standard rates, you can also use the VAT calculator.
Is anything I enter uploaded?
No. All calculations run in your browser and nothing is sent or stored on a server.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.