METHOD & GUIDANCE
How this calculation works
Enter figures from the same period and on a consistent sales tax-inclusive or sales tax-exclusive basis. Tool IQ recalculates every output immediately; nothing you enter is saved or sent to us.
How to use the result
Enter the applicable combined state and local rate, then keep the subtotal, tax and final customer total separate.
Worked example
At the opening 8.25% combined rate, a 100 taxable subtotal produces 8.25 tax and a 108.25 total.
Common mistakes
- Using a state rate without the applicable local rate.
- Assuming every product or customer is taxable.
- Treating sales tax collected as business revenue.
Frequently asked questions
Is this calculator free?
Yes. It requires no account and stores no calculation inputs.
Can I use the answer for a formal filing?
No. It is a planning estimate, not accounting, tax, legal or investment advice. Confirm material decisions with a qualified professional.
Should I include sales tax?
Use a consistent basis throughout. Businesses that recover input tax commonly model net figures; consumer-facing prices are often considered gross.
Continue the decision
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Method reviewed 26 July 2026. Figures are illustrative and calculated locally in your browser.