Sales Tax & GST Calculator
The Sales Tax Calculator handles any consumption tax — US state sales tax, Canadian GST/HST, Australian GST, New Zealand GST, or any custom rate. Enter a price and tax rate, choose whether to add tax or extract it from a total, and get an instant breakdown.
Educational estimate. Calculator results are for planning and information only, not financial, tax, medical, legal, or engineering advice. Verify important decisions with official sources or a qualified professional.
Sales Tax & GST Calculator
Add or Remove Tax from Any Price
📐 Formula & Method
Add Tax (Tax Exclusive)
Use when a price is shown before tax (most common in the US and B2B transactions).
Remove Tax (Tax Inclusive / Reverse)
Use when a price already includes tax and you want to find the original pre-tax amount (common in UK VAT and Australian GST pricing).
📋 How to Use
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1
Enter the price or total amount.
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2
Select the appropriate tax rate from the list, or choose Custom Rate to enter your own.
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3
Choose whether to add tax to the price, or extract tax from a tax-inclusive total.
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4
Click Calculate to see the tax amount, pre-tax price, and total.
US Sales Tax, Canadian GST, and Australian GST Explained
In the United States, sales tax is set at the state and local level — there is no federal sales tax. Rates vary widely: Oregon, Montana, New Hampshire, and Delaware have no state sales tax (0%). California has the highest at 7.25% base (some districts exceed 10% combined). The US average combined state + local sales tax rate is approximately 7.0%. Unlike UK VAT, US prices are typically shown pre-tax on price tags.
Canada's Goods and Services Tax (GST) is a federal tax of 5% applied to most goods and services. Provinces add their own taxes: Ontario and several Atlantic provinces charge Harmonized Sales Tax (HST) combining federal and provincial tax — Ontario HST is 13%, Nova Scotia and New Brunswick is 15%. British Columbia, Alberta, Saskatchewan, and Manitoba charge GST plus a separate Provincial Sales Tax (PST). Alberta has no PST, making its combined rate just 5%.
Australia's GST (Goods and Services Tax) is a federal 10% tax on most goods and services. New Zealand's GST is 15%. Unlike the US, prices in Australia and New Zealand are legally required to be displayed inclusive of GST (the total price including tax must be shown). This makes the "reverse GST" or "remove GST" calculation useful for businesses needing to split pricing into pre-tax and tax components for accounting.
UK VAT (Value Added Tax) is charged at 20% on most goods and services. Reduced rate (5%) applies to domestic fuel, children's car seats, and some energy-saving products. Zero rate (0%) applies to most food, children's clothing, and books. Businesses with annual taxable turnover above £90,000 (2024-25 threshold) must register for VAT. The UK VAT Calculator is available as a separate dedicated tool on this site.
🔬 Methodology & Accuracy
Formula: Uses the standard mathematical formula shown in the Formula & Method section above. All computations run client-side in your browser — no data is sent to our servers.
Data sources: Tax bands, contribution limits and regulatory rates are taken from official US (IRS, SSA) and UK (HMRC, gov.uk) publications for the current tax year, and updated when bands change.
Last reviewed: June 2026 · Accuracy: Results are precise to two decimal places using IEEE-754 double-precision arithmetic. Intended for educational and planning use only.
For informational purposes only. Results are estimates based on the inputs and formulas provided. For financial, tax, medical, or legal decisions, consult a qualified professional. Rates and regulations change — always verify current figures with official sources.