Forward vs reverse calculation
Businesses quote prices pre-tax while customers pay post-tax, so both directions matter: forward for invoicing, reverse for analyzing receipts or separating VAT/GST-style taxes embedded in prices.
Sales Tax Calculator
Add or remove sales tax: pre-tax price, tax amount and gross total both directions.
Enter your details and press Calculate to see results.
Formula
With tax: amount × (1 + rate) · Tax inside total: total × rate ÷ (1 + rate)
Example
$100 plus 8.25% tax = $108.25. A $108.25 receipt at 8.25% contains $8.25 tax.
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Frequently asked questions
Does this work for VAT?
Yes — VAT-inclusive prices are the 'remove' mode with the VAT rate entered.
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