Sales Tax Calculator
Add sales tax to a price, extract the pre-tax price from a tax-inclusive total, or compare what the same purchase would cost across several different tax rates.
Enter tax rates to compare (e.g. rates from different states or regions)
All calculations run in your browser. Nothing is sent to a server. Rates shown are examples, always confirm the actual rate for your location.
Adding tax to a price is a simple calculation, similar in spirit to a basic markup on the Markup Calculator, but two related questions come up just as often: what was the price before tax was added to a receipt total, and how much would the same item actually cost in a different tax jurisdiction. The three modes below cover each of those separately, so switching between them replaces re-deriving the formula each time.
Related Calculators
How It Works
Pre-tax price = Total ÷ (1 + tax rate)
A $49.99 item with 8.25% tax: 49.99 × 1.0825 = $54.12 total. Working backward from $54.12 at the same rate returns the original $49.99.
Practical Situations This Handles
Comparing prices between an online store showing tax-exclusive pricing and a local store showing tax-included pricing, checking a receipt against an expected total, or estimating the real cost of a purchase before traveling to a different tax jurisdiction are all situations where knowing how to move between pre-tax and post-tax prices matters.
Online Versus In-Store Shopping
Online retailers sometimes display prices before tax and calculate the final amount at checkout, while a local store's shelf price may already include tax. Comparing the two fairly means adjusting one to match the other's basis, otherwise the online price looks artificially cheaper than it actually ends up being.
Travel and Cross-Border Purchases
Tax rates vary significantly between states, provinces, and countries. Someone comparing the cost of the same purchase while traveling, or deciding where to buy something before crossing a state line, benefits from being able to quickly see the total under a few different rates side by side rather than calculating each one separately by hand.
Budgeting and Receipt Checking
Checking that a receipt matches what was expected, or budgeting for a large purchase where the tax amount meaningfully changes the total, both rely on being able to move cleanly between pre-tax and post-tax figures without second-guessing the arithmetic. If the original price itself is also uncertain, working backward with the Reverse Percentage Calculator can help reconstruct it from a discounted or marked-up starting point.
Common Mistakes
Frequently Asked Questions
How do I calculate sales tax on a purchase?
Multiply the price by the tax rate as a decimal, then add that to the original price. The "Add Tax to a Price" mode above does this in one step.
How do I find the price before tax from a total on a receipt?
Divide the total by (1 plus the tax rate as a decimal). Subtracting the tax percentage directly from the total gives an incorrect result.
Do all products get taxed at the same rate?
No. Many places apply different rates or exemptions to categories like groceries, clothing, or medicine. The rate used should match the specific item and location.
How can I compare the real cost of an item across different tax rates?
Use the "Compare Tax Rates" mode above, enter the pre-tax price once, and list the rates you want to compare side by side to see the total under each one.
Why might the tax on my receipt not match a quick mental estimate?
Combined tax rates often include several layers, such as a state rate plus a local or county rate, which can add up to an unusual-looking number like 8.25% rather than a round figure. Checking the actual combined rate for the specific location is more reliable than guessing.