METHOD & GUIDANCE
How this calculation works
Keep tax-inclusive and tax-exclusive figures consistent, and use the rules and rate that apply to the relevant jurisdiction and transaction. 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 the sales tax 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.
Does this calculator choose the correct sales tax rate for me?
No. Enter the combined state and local rate that applies to the transaction. Taxability and sourcing can vary by product, customer and jurisdiction.
Does the calculator find the correct sales-tax rate from an address?
No. Enter the combined rate that applies after confirming state and local sourcing, product taxability and any customer exemption.
Is collected sales tax business revenue?
It should be tracked separately from operating revenue and reconciled to the amounts the seller is required to remit.
Continue the decision
- Profit Margin Calculator — See profit, margin and markup from one sale.
- Freelance Rate Calculator — Turn an income goal into a sustainable day rate.
Popular small-business decision paths
- Separate tax from an inclusive total
- Keep collected sales tax out of operating cash
- Review the US sales-tax decision guide
Get the free quarterly tax planner →
Optional email capture; this calculator remains free.
Official sources and checks
- US Small Business Administration: pay taxes — Starting point for federal, state and local business-tax responsibilities.
Method reviewed 5 August 2026. Figures are illustrative and calculated locally in your browser. Official sources are linked where a rule or obligation affects how the result should be used. Read the Tool IQ calculation standard for our checking process, limitations and corrections policy.