Reverse Tax Excel Formula
Use spreadsheet formulas when you need to reverse calculate tax across receipts, invoices, product prices, or ecommerce exports.
Interactive calculator
Calculate tax backwards
$120.00 at 20% Tax: pre-tax $100.00, Tax $20.00.
Estimate only. Verify official rates before filing, invoicing, or making tax decisions.
Primary query
reverse tax excel formula
Default rate
20%
Rate source
Manual rate input
Last updated
2026-05-14
Formula
How reverse tax calculation works
If A2 contains the tax-inclusive total and B2 contains the tax rate formatted as a percentage, divide A2 by 1 plus B2. The same formulas work in Excel and Google Sheets.
Pre-tax Price = Total Price / (1 + Tax Rate)
Tax Amount = Total Price - Pre-tax Price
Example
Excel example with A2 = 120 and B2 = 20%
- Pre-tax formula: =A2/(1+B2)
- Tax amount formula: =A2-(A2/(1+B2))
- Check formula: =(A2/(1+B2))*(1+B2)
- Result: pre-tax price 100.00 and tax amount 20.00
Spreadsheet
Excel and Google Sheets formulas
Pre-tax price
=A2/(1+B2)Use this when A2 is the tax-inclusive total and B2 is formatted as a percentage.
Tax amount
=A2-(A2/(1+B2))This returns the tax portion included in the total price.
FAQ
reverse tax excel formula 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.
What is the Excel formula to remove tax from a total?
If A2 is the total and B2 is the tax rate percentage, use =A2/(1+B2).
Does the same formula work in Google Sheets?
Yes. Google Sheets uses the same formula: =A2/(1+B2) for the pre-tax price and =A2-(A2/(1+B2)) for the tax amount.
Should B2 contain 20%, 0.2, or 20?
Use 20% or 0.2. If your sheet stores the rate as 20, divide it by 100 in the formula, for example =A2/(1+B2/100).
How do I verify a spreadsheet reverse tax formula?
Multiply the calculated pre-tax price by 1 plus the rate. The check should return the original tax-inclusive total, allowing for rounding.
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