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Sales Tax Calculator

Calculate sales tax — add tax to a price or back it out of a total.

100% Free No signup Privacy-friendly Calculators
Updated Sep 2026
Net
Sales Tax
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How to use Sales Tax Calculator

  1. Enter the price and your local tax rate — tax amount and total compute instantly.
  2. For receipts and totals, use the reverse mode: enter the tax-included amount to extract the pre-tax price.
  3. Find your combined rate (state + local) on your state's revenue site — it varies by city and county.
  4. Copy the split into your expense report or books — pre-tax and tax belong in separate columns.

What is Sales Tax Calculator?

A sales tax calculator works the tax equation both directions: forward — price × (1 + rate) gives the register total ($49.99 at 8.25% → $54.11) — and reverse, extracting the tax from a tax-included total: pre-tax = total ÷ (1 + rate), so a $54.11 receipt at 8.25% contained $49.99 of goods and $4.12 of tax.

The reverse direction is the one done wrong constantly: subtracting 8.25% of the total overshoots, because the tax was computed on the smaller pre-tax amount. Dividing by 1.0825 is correct — the difference matters on every expense report and invoice reconciliation.

About the Sales Tax Calculator

Enter a price and tax rate to get the tax amount and total — or enter a tax-included total to break out the pre-tax price and tax paid, with the correct divide-not-subtract math.

US context for the rate box: sales tax combines state + local rates, ranging from 0% (Oregon, Montana, New Hampshire, Delaware; Alaska has no state rate) to combined rates above 9–10% (parts of Louisiana, Tennessee, Washington state cities). Your rate is the one at the point of sale — online sellers meanwhile face destination-based rules post-Wayfair, which is why business use of the reverse calculation (extracting tax from gross receipts per jurisdiction) is so common.

Note the US quirk that surprises visitors: shelf prices exclude tax — the register adds it — unlike VAT countries where displayed prices are final. Same math, opposite conventions; our VAT and GST calculators handle those systems' terminology.

Frequently Asked Questions

Multiply by the rate: $80 × 0.0825 = $6.60 tax, $86.60 total. One step: price × 1.0825. The rate to use is the combined state + local rate where the sale happens.
Divide by (1 + rate): $86.60 ÷ 1.0825 = $80.00 pre-tax. Subtracting 8.25% of the total instead gives $79.46 — wrong, because the tax was charged on $80, not on $86.60.
Oregon, Montana, New Hampshire and Delaware have none; Alaska has no state tax but allows local ones. At the other end, combined rates in parts of Louisiana and Tennessee exceed 9.5%.
Convention plus complexity — with thousands of overlapping state/county/city rates, national retailers can't print one tax-included price. VAT countries mandate tax-included display; the US adds at the register.
Generally yes since the 2018 Wayfair ruling — sellers above a state's threshold must collect that state's tax based on the delivery address. The era of tax-free online shopping is over for major retailers.

Learn more

How to Calculate Sales Tax, VAT and GST

Adding tax to a price is simple once you know the steps. Here is how to calculate sales tax, VAT and GST — and how to work backwards from a total.

Read the guide

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