Skip to content
Free Calculator logoFree Calculator

Sales Tax Calculator

Add sales tax or find the pre-tax price from a tax-inclusive total.

How do I add or remove sales tax from a price?

To add tax, multiply the net price by one plus the rate; to remove it, divide the gross price by one plus the rate.

Formula: Added tax = pre-tax amount × rate ÷ 100. Reverse tax divides the inclusive total by (1 + rate ÷ 100).

Read the guide: how to calculate a tip

Calculation

Amount is required.

Sales tax rate is required.

Press Calculate, or Enter in any field.

Add 8.25% tax to $100

Tax is $8.25 and the total is $108.25.

Complete the required fields to see the result.

What this calculator does

Calculate tax and totals in either direction using a sales tax percentage you provide.

Use it to turn Calculation, Amount, Sales tax rate into a checked result you can compare, copy, or rerun with different assumptions.

The page shows the formula, a numeric worked example, and the assumptions that affect this finance calculation.

Inputs and what they mean

Calculation
— choice value.
Amount
— number value.
Sales tax rate
— number value.

How to use it

  1. Choose whether to add tax or remove included tax.
  2. Enter the amount and tax rate.
  3. Read the tax and total or pre-tax amount.

Formula

Added tax = pre-tax amount × rate ÷ 100. Reverse tax divides the inclusive total by (1 + rate ÷ 100).

Inputs used: Calculation, Amount, Sales tax rate.

Edge handling: Amount is required.; Amount cannot be negative.; Amount must be no more than 1000000000000.; Sales tax rate is required.; Sales tax rate cannot be negative..

Worked example

Add 8.25% tax to $100

  1. Start with Calculation: add, Amount: 100, Sales tax rate: 8.25.
  2. Apply the method: Added tax = pre-tax amount × rate ÷ 100. Reverse tax divides the inclusive total by (1 + rate ÷ 100).
  3. Tax is $8.25 and the total is $108.25.

Reading the result

The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.

Limitations and assumptions

  • Inputs outside the supported range are rejected rather than forced into a result.
  • The result depends on the values you enter for this sales tax calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.

Common questions

How do I add or remove sales tax from a price?

To add tax, multiply the net price by one plus the rate; to remove it, divide the gross price by one plus the rate. Check the formula, example, and limitations on this page before using the result for a real finance decision.

Does this know my local tax rate?

No. Enter the applicable combined rate for your location.

Why is reverse tax not simple subtraction?

Because the tax percentage is based on the pre-tax price, not the inclusive total. Check the formula, example, and limitations on this page before using the result for a real finance decision.

Is this an income tax calculator?

No. This tax calculator handles sales tax, VAT and GST on a price. Income tax depends on country-specific brackets and deductions, which this page does not model.

How do I use the Sales Tax Calculator?

Enter the required values for Calculation, Amount, Sales tax rate. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.

What formula does the Sales Tax Calculator use?

Added tax = pre-tax amount × rate ÷ 100. Reverse tax divides the inclusive total by (1 + rate ÷ 100). The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.

Cite this page

APA

Free Calculator. (n.d.). Sales Tax Calculator. https://freecalculator.tech/tools/sales-tax-calculator

MLA

"Sales Tax Calculator." Free Calculator, https://freecalculator.tech/tools/sales-tax-calculator.

Link

Sales Tax Calculator — Free Calculator, https://freecalculator.tech/tools/sales-tax-calculator

Related tools

Calculate a sale price, savings, and optional additional discount.

Finance

Calculate a tip, total bill, split per person, and common tip comparisons.

Finance

Convert hourly pay to annual, monthly, weekly, and daily gross income.

Finance

Convert annual salary to hourly, daily, weekly, and monthly gross pay.

Finance

Estimate compound growth with contributions, scenarios, a chart, and yearly table.

Finance

Estimate mortgage payments, total interest, costs, and an amortization schedule.

Finance