How to use the VAT & Sales Tax Calculator
- Choose whether to add tax or remove it.
- Enter the amount.
- Enter the tax rate (for example 20% for standard UK VAT).
- Read the net price, tax amount and gross price.
What does this tool do?
Adding tax is straightforward: multiply by (1 + rate). Removing it is where mistakes happen. To find the pre-tax price you divide by (1 + rate) — you don't subtract the rate. A $120 price with 20% VAT included was $100 before tax, not $96.
VAT, GST and sales tax all work the same way mathematically, so this calculator works for any of them.
Why use it?
- Get the net price from a receipt right every time.
- Prepare invoices with correct tax lines.
- Works with any country's rate.
Examples
Some common calculations:
| Task | Calculation | Result |
|---|---|---|
| Add 20% VAT to $100 | 100 × 1.20 | $120 |
| Remove 20% VAT from $120 | 120 ÷ 1.20 | $100 (tax $20) |
| Add 18% GST to ₹5,000 | 5,000 × 1.18 | ₹5,900 |
| Remove 8.25% sales tax from $54.13 | 54.13 ÷ 1.0825 | $50.00 |
The formula
Add tax: Gross = Net × (1 + rate ÷ 100)
Remove tax: Net = Gross ÷ (1 + rate ÷ 100)
Accuracy and limits
- Tax rates change and vary by product and region. Check your local tax authority for the correct rate.
Privacy
The calculation happens instantly in your browser. The numbers you enter are not sent to our servers or saved. There's no account to create and nothing to install.
Frequently asked questions
Why can't I just subtract 20% to remove VAT?
Because the 20% was calculated on the smaller, pre-tax amount. Subtracting 20% of the bigger, tax-inclusive amount takes off too much.
Last reviewed by the M2Toolkit team.