VAT calculator

At 20% VAT, 100 net becomes 120 gross, and removing VAT from 120 gross gives 100 net with 20 VAT. Choose Add VAT for a price before tax or Remove VAT for a price that already includes it.

What this calculator does

This VAT calculator separates an amount into net, VAT and gross totals. Net means before VAT, gross means including VAT, and the VAT amount is the difference between them. Enter the amount, select the correct direction and use the rate that applies to the transaction. The working shows the multiplier so you can check how the result was obtained.

The UK standard VAT rate is 20% and the reduced rate is 5%. Those are rate options, not a determination of which goods or services qualify. The calculator also works arithmetically with other VAT, sales tax or GST rates. The 21% and 23% preset buttons are convenient examples, not a statement of any country's current rules. Confirm the applicable rate and treatment separately.

Formula

Add VAT: gross = net × (1 + rate ÷ 100)

Or in one step: Remove VAT: net = gross ÷ (1 + rate ÷ 100)

In plain English, add VAT by multiplying the net amount by one plus the rate written as a decimal. Remove VAT by dividing the gross amount by that same multiplier. Then find VAT by taking net away from gross. At 20% the multiplier is 1.2, while at 5% it is 1.05. The rate must be zero or more.

Worked example

An item has a net price of 100 and VAT at 20%. Multiply 100 by 1.2 to get a gross price of 120. The VAT amount is 120 − 100 = 20. Checking in reverse, 120 ÷ 1.2 returns the net price of 100.

Worked example: a VAT-inclusive bill

A bill totals 240 including VAT at 20%. The gross total represents 120% of the net amount, so divide 240 by 1.2 to get 200 net. The VAT is 240 − 200 = 40. Check forwards by adding 20% of 200, which is 40, to reach 240 again.

Taking 20% directly off 240 would give 192, not 200. That mistake uses the wrong base. At 20%, the tax portion of an inclusive total is one sixth of that total, rather than one fifth. The multiplier method works without memorising a special fraction for every possible rate.

Worked example: applying a 5% rate

Suppose a transaction to which a 5% rate applies has a net amount of 200. The VAT is 200 × 0.05 = 10, and the gross amount is 210. To check the reverse direction, choose Remove VAT and divide 210 by 1.05. The answer is 200 net with 10 VAT.

Negative amounts can be entered for arithmetic comparisons such as a credit reversing an earlier charge. The signs of net, tax and gross then follow the amount. The chart is intended for non-negative totals. This does not determine whether a credit note is valid, what details it needs, or how it should be reported.

VAT formulas in Excel and Google Sheets

With an amount in A1 and a rate entered as an ordinary number such as 20 in B1, use =A1*(1+B1/100) to add VAT. To remove VAT from a gross amount in A1, use =A1/(1+B1/100). Calculate the VAT amount as gross minus net in a separate cell.

If B1 contains the percentage-formatted value 20%, omit the extra division by 100: use =A1*(1+B1) or =A1/(1+B1). Both Excel and Google Sheets follow these conventions. Keep the underlying cells numeric, label net and gross clearly, and apply currency formatting without rounding intermediate calculations unnecessarily.

Everyday examples

Example	Answer	Try it
Add 20% VAT to £100 net	£120.00
Remove 20% VAT from £120 gross	£100.00
Add 5% VAT to £200 net	£210.00
Remove 5% VAT from £210 gross	£200.00

Common mistakes

Taking 20% off a VAT-inclusive amount to remove 20% VAT. The original VAT was based on the smaller net amount, not the gross total.
Entering a gross price in Add VAT mode. That adds tax again rather than extracting the amount already included.
Assuming every line on a bill has the same VAT treatment. Split different rates and separately charged items before calculating totals.
Confusing a zero-rate calculation with a legal classification. A numerical rate of zero does not establish whether a transaction is zero-rated, exempt or outside scope.

Common questions

How do I add 20% VAT?

Multiply the net price by 1.2. A net amount of 100 becomes 120 gross, including 20 VAT. In Add VAT mode, enter 100 as the amount and 20 as the VAT rate. The breakdown shows all three figures.

How do I remove VAT from an inclusive price?

Divide the inclusive price by one plus the VAT rate as a decimal. At 20%, divide by 1.2. An inclusive amount of 120 gives 100 net and 20 VAT. Removing VAT does not mean reducing the gross price by the stated rate.

How much VAT is included in 120 at 20%?

20. First find the net amount: 120 ÷ 1.2 = 100. Then calculate 120 − 100 = 20. Equivalently, the included VAT is gross × rate ÷ (100 + rate), which here is 120 × 20 ÷ 120.

What is the difference between net and gross?

For this calculator, net is the amount before VAT and gross is the amount including VAT. Their difference is the VAT amount. Those labels can mean other things in other contexts, such as pay calculations, so make sure you are comparing like amounts.

Can I use a different sales tax or GST rate?

Yes. Enter the actual applicable rate instead of choosing a preset. The same multiplier arithmetic works for a single percentage tax added to a base price. It does not decide which rate applies or handle separate fixed charges and multiple tax bases automatically.

What happens at a 0% VAT rate?

The net and gross amounts are identical and the VAT amount is zero. For example, 125 remains 125 in either mode. That is the mathematical outcome; it does not establish the tax classification or reporting requirements of a particular transaction.

Why might my invoice differ by a penny?

Rounding each invoice line can produce a different total from rounding once after summing unrounded amounts. Money display here uses two decimal places, while internal decimal calculations retain more precision. Follow the rounding method required for the actual invoice rather than treating this comparison as tax advice.

Last reviewed 8 November 2026. Results use exact decimal arithmetic and are rounded once for display.