Already have the total? Enter it below and this calculator works backwards to the pre-tax subtotal and the exact tax amount, for any US state or Canadian province.
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This formula has no tax components.
Each example starts from a $100.00 subtotal and shows the total you would have paid — then reverses it back to the subtotal and tax, state by state.
Paid 100.00 total? Subtotal is 100.00 (tax: 0.00).
Paid 104.00 total? Subtotal is 100.00 (tax: 4.00).
Paid 106.50 total? Subtotal is 100.00 (tax: 6.50).
Paid 105.60 total? Subtotal is 100.00 (tax: 5.60).
Paid 107.25 total? Subtotal is 100.00 (tax: 7.25).
Paid 102.90 total? Subtotal is 100.00 (tax: 2.90).
Paid 106.35 total? Subtotal is 100.00 (tax: 6.35).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 100.00 total? Subtotal is 100.00 (tax: 0.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 104.00 total? Subtotal is 100.00 (tax: 4.00).
Paid 104.00 total? Subtotal is 100.00 (tax: 4.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 106.25 total? Subtotal is 100.00 (tax: 6.25).
Paid 107.00 total? Subtotal is 100.00 (tax: 7.00).
Paid 106.50 total? Subtotal is 100.00 (tax: 6.50).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 104.45 total? Subtotal is 100.00 (tax: 4.45).
Paid 106.25 total? Subtotal is 100.00 (tax: 6.25).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 105.50 total? Subtotal is 100.00 (tax: 5.50).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 106.88 total? Subtotal is 100.00 (tax: 6.88).
Paid 104.23 total? Subtotal is 100.00 (tax: 4.23).
Paid 107.00 total? Subtotal is 100.00 (tax: 7.00).
Paid 100.00 total? Subtotal is 100.00 (tax: 0.00).
Paid 104.75 total? Subtotal is 100.00 (tax: 4.75).
Paid 105.00 total? Subtotal is 100.00 (tax: 5.00).
Paid 105.50 total? Subtotal is 100.00 (tax: 5.50).
Paid 100.00 total? Subtotal is 100.00 (tax: 0.00).
Paid 106.63 total? Subtotal is 100.00 (tax: 6.63).
Paid 105.00 total? Subtotal is 100.00 (tax: 5.00).
Paid 106.85 total? Subtotal is 100.00 (tax: 6.85).
Paid 104.00 total? Subtotal is 100.00 (tax: 4.00).
Paid 105.75 total? Subtotal is 100.00 (tax: 5.75).
Paid 104.50 total? Subtotal is 100.00 (tax: 4.50).
Paid 100.00 total? Subtotal is 100.00 (tax: 0.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 107.00 total? Subtotal is 100.00 (tax: 7.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 104.50 total? Subtotal is 100.00 (tax: 4.50).
Paid 107.00 total? Subtotal is 100.00 (tax: 7.00).
Paid 106.25 total? Subtotal is 100.00 (tax: 6.25).
Paid 106.10 total? Subtotal is 100.00 (tax: 6.10).
Paid 105.30 total? Subtotal is 100.00 (tax: 5.30).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 106.50 total? Subtotal is 100.00 (tax: 6.50).
Paid 105.00 total? Subtotal is 100.00 (tax: 5.00).
Paid 106.00 total? Subtotal is 100.00 (tax: 6.00).
Paid 104.00 total? Subtotal is 100.00 (tax: 4.00).
Enter the total amount you already paid — the one that includes tax — and select your province or state. The calculator works backwards through the tax formula to show the original subtotal and the exact tax amount.
This is useful when a receipt or invoice only shows a total and you need the pre-tax cost — for expense reports, bookkeeping, or splitting a bill where tax needs to be backed out separately.
Yes. The calculator works backwards through the same rounding rules used for the forward calculation, so the result matches what a forward calculation on that subtotal would have produced, to the cent.
Yes — use the sales tax calculator, linked at the top of this page, to add GST, HST, QST, PST, or US sales tax to a subtotal.