Sales Tax Calculator: Forward & Reverse Tax Estimates

Calculate sales tax on net prices or reverse-calculate pre-tax amounts from gross receipts.

Enter Calculation Values

Enter original price before sales tax or VAT is added.
$
Enter your local, state, or provincial combined tax rate (e.g. 8 for 8.00%).
%

Calculation Results

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Total Price (Tax Included)
$108.00
  • Sales Tax Amount: $8.00
  • Pre-Tax Base Price: $100.00
  • Applied Tax Rate: 8.00%

Sales Tax Mathematical Formulas

Forward Mode:
Tax Amount = Pre-Tax Price × (Tax Rate % / 100)
Total Price = Pre-Tax Price + Tax Amount

Reverse Mode (Tax Extraction):
Pre-Tax Price = Total Price / (1 + Tax Rate % / 100)
Tax Amount = Total Price - Pre-Tax Price
Worked Example: For a $100.00 pre-tax item with an 8% tax rate:
1. Tax Amount = $100 × 0.08 = $8.00
2. Total Price = $100 + $8 = $108.00
3. Reverse check: $108 / 1.08 = $100.00 base.

Disclaimer: Tax rates vary widely by state, county, municipality, and product category. This is a mathematical estimation tool and does not provide legal or tax advice.

Frequently Asked Questions

Does this calculator contain live US state tax rates?

No. Local sales tax rates change frequently and depend on exact destination zip codes. You should input your specific local combined rate for exact results.

How do I extract tax from a receipt total?

Select "Extract Pre-Tax Price from Total (Reverse)" mode, enter the final charge and the applicable tax rate.

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Helpful Reading

Learn more about strategic pricing in our guide: Business Pricing Masterclass.