Reverse Sales Tax Calculator
Use this reverse sales tax calculator when a receipt or checkout total already includes sales tax.
Interactive calculator
Calculate tax backwards
$86.75 at 7.25% Sales tax: pre-tax $80.89, Sales tax $5.86.
Estimate only. Verify official rates before filing, invoicing, or making tax decisions.
Primary query
reverse sales tax calculator
Default rate
7.25%
Rate source
Reference default; local sales tax varies by address
Last updated
2026-05-14
Formula
How reverse tax calculation works
Start with the tax-inclusive total, then divide by 1 plus the tax rate. Use the tax rate as a decimal in the formula.
Pre-tax Price = Total Price / (1 + Tax Rate)
Tax Amount = Total Price - Pre-tax Price
Example
$86.75 with 7.25% sales tax
- Tax multiplier = 1 + 7.25% = 1.0725
- Pre-tax price = 86.75 / 1.0725 = 80.89
- Sales tax amount = 86.75 - 80.89 = 5.86
FAQ
reverse sales tax calculator questions
How do you reverse calculate tax?
Divide the tax-inclusive total by 1 plus the tax rate. For example, with a 20% tax rate, divide the total by 1.20.
What is the reverse tax formula?
Pre-tax price = total price / (1 + tax rate). Tax amount = total price - pre-tax price.
Is this calculator tax advice?
No. This is an educational calculator for estimates. Confirm official rates and rules before filing, invoicing, or making compliance decisions.
How do I calculate reverse sales tax from a receipt?
Use the receipt total as the tax-inclusive amount, then divide by 1 plus the sales tax rate as a decimal.
What if I only know the total and the tax amount?
Subtract the tax amount from the total to get the pre-tax price. You can then divide the tax amount by the pre-tax price to estimate the sales tax rate.
Should I use the state rate or the local combined rate?
Use the combined rate for the exact store, delivery address, or jurisdiction when you have it. State-only defaults are useful for examples, but many US locations add local sales tax.
Is reverse sales tax the same as subtracting the rate?
No. If a total already includes tax, divide by 1 plus the rate. Subtracting the percentage from the total treats the tax as a percentage of the gross amount, which is not how sales tax is normally added.
Can I use this for tax-inclusive ecommerce prices?
Yes, if the same sales tax rate applies to the total. For mixed carts with different taxability or rates, calculate each taxable line separately.
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