GST Calculator

Add GST to a price or remove it from a total.

GST calculation details

Use Add GST for tax-exclusive amounts or Remove GST when the amount already includes tax.

Currency

Use this when your amount is before GST.

GST rates vary by country, product type, and tax rules.

Common rate shortcuts

GST-inclusive total

£110.00

Final amount after adding GST.

GST-exclusive amount

£100.00

Net amount before GST.

GST amount

£10.00

Tax portion at 10%.

GST rate

10%

Rate entered for this calculation.

Calculation mode

Add GST

Tax-exclusive to gross.

Original amount

£100.00

Amount entered above.

Net / tax / gross breakdown

Net

£100.00

GST

£10.00

Gross

£110.00

Check whether the listed price already includes GST before adding tax.
Updated May 2026Formula verifiedReviewed for accuracy

Insights

What your GST result means

Calculation summary

Adding 10% GST to £100.00 gives a total of £110.00.

GST portion

The GST amount in this calculation is £10.00.

Removing GST correctly

The GST portion of a GST-inclusive price is not found by simply subtracting 10% from the total.

Invoice clarity

Separating net amount, GST amount, and gross total can help reduce pricing and bookkeeping confusion.

Basics

What GST means

Goods and Services Tax

GST stands for Goods and Services Tax and may apply to taxable goods and services.

Added to taxable sales

GST is usually added to the taxable price paid by the customer.

Collected by businesses

Registered businesses may collect GST and report it under local tax rules.

Rules vary

Rates, exemptions, and registration thresholds depend on jurisdiction.

Compare

Adding GST vs removing GST

Adding GST

Start with a GST-exclusive amount. GST amount equals net amount times GST rate, and gross amount equals net plus GST.

Removing GST

Start with a GST-inclusive amount. Divide by one plus the GST rate to find the net amount, then subtract to find GST.

Pricing

GST-inclusive vs GST-exclusive prices

GST-exclusive price

Price before GST.

GST amount

Tax portion added to the net price.

GST-inclusive price

Final price including GST.

Example: £100.00 exclusive + £10.00 GST = £110.00 inclusive.

Use cases

Common GST rates and use cases

GST rates are not universal. Choose the relevant rate for your jurisdiction and product type.

Invoices

Show net, GST, and gross totals clearly.

Quotes

Clarify whether quoted prices include or exclude GST.

Receipts

Review the tax component of a GST-inclusive purchase.

Ecommerce pricing

Check customer-facing totals before publishing prices.

Freelance billing

Separate service fees and tax where applicable.

Bookkeeping

Track taxable amounts and GST portions for records.

Tax notes

Business invoicing and tax notes

This calculator handles the arithmetic; tax treatment depends on your local rules.

Invoice display

Businesses may need to show GST separately on invoices depending on registration status and local requirements.

Different categories

Some products or services may be GST-free, exempt, zero-rated, or taxed differently.

Confirm obligations

GST registration rules vary by jurisdiction. Check your local tax authority or consider speaking with an accountant.

Formula

GST formula explanation

Add GST

Gross = Net × (1 + GST Rate)

Used when the amount does not yet include GST.

Remove GST

Net = Gross ÷ (1 + GST Rate)

Used when the amount already includes GST.

GST amount

GST = Gross − Net

Shows the tax portion included in or added to the price.

The GST rate in formulas should be used as a decimal. For example, 10% GST is 0.10, so adding GST to 100 is 100 × 1.10 = 110.

FAQ

GST calculator questions

GST stands for Goods and Services Tax. It is a consumption tax that may be added to taxable goods and services, depending on jurisdiction and product type.