How do I find the pre-GST price from an inclusive total?

Divide the total by (1 + GST rate as a decimal). For a 5% rate: pre-GST price = total ÷ 1.05.

Is GST the same as VAT or sales tax?

GST, VAT, and sales tax all serve a similar purpose (taxing consumption) but differ by country in how and where they're collected — for a single purchase, the percentage math works the same way.

GST Calculator

Calculate Goods and Services Tax (GST) — add GST to a price, or back it out of a GST-inclusive price.

Mode

Price before GST

GST rate

GST Amount

$5.00

Total Price

$105.00

How It Works

Adding GST

GST amount = price × GST rate. The GST-inclusive price is the original price plus that GST amount.

Removing GST from an inclusive price

To find the pre-GST price from a GST-inclusive total, divide by (1 + GST rate) — not by simply subtracting the percentage.

Example Calculation

A $100 price with 5% GST has $5 of GST, for a $105 total.

Common Mistakes

Subtracting the GST percentage directly from a GST-inclusive total instead of dividing by (1 + rate).
Using the wrong rate for goods that are GST-exempt or zero-rated in your jurisdiction.

Frequently Asked Questions

How do I find the pre-GST price from an inclusive total?: Divide the total by (1 + GST rate as a decimal). For a 5% rate: pre-GST price = total ÷ 1.05.
Is GST the same as VAT or sales tax?: GST, VAT, and sales tax all serve a similar purpose (taxing consumption) but differ by country in how and where they're collected — for a single purchase, the percentage math works the same way.