Simple interest
Money & business
How to calculate add sales tax
To add a tax rate, multiply the net price by one plus the rate divided by 100. At an entered rate of 20%, a net price of 100 becomes 120.
Formula
net × (1 + rate ÷ 100); enter your applicable rate
Worked example
- Net amount
- 100
- Tax rate (%)
- 20
Applying the formula to these values gives 120 .
What should I check?
The example rate is illustrative. Rates, exemptions and treatment differ by transaction and jurisdiction; this tool does not determine which rate applies.
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