Unit Converter
Sales Tax Calculator
Estimate sales tax and total checkout price from a subtotal and tax rate.
Formula and usage notes
tax amount = subtotal x tax rate; total = subtotal + tax amount.
Estimate sales tax and total checkout price from a subtotal and tax rate.
Practical examples
75 at 8.25% tax totals 81.19 before optional fees.
Use the combined state and local rate when both apply.
Shipping, tips, and service fees can have different tax rules.
Frequently asked questions
What inputs does this calculator need?
Subtotal, Tax rate.
How should I round the result?
Keep extra digits while comparing values, then round for the final decision or report.
Can I reuse the result in another calculation?
Yes, but preserve the original inputs and units so the next calculation stays traceable.