Tax
GST Calculator
Add 15% GST to a price or find the GST and the GST-exclusive amount inside a GST-inclusive price (3/23), to the cent.
Result
Updates as you typePrice including GST
$115.00
- GST (15%)
- $15.00
- Price excluding GST
- $100.00
How it's calculated
GST is charged at 15% on the GST-exclusive price of a standard-rated supply. Working back from a GST-inclusive price, the GST is 3/23 of the total, because 15 ÷ 115 = 3 ÷ 23.
Worked example
$2,500.00 at 15% GST:
- If it excludes GST: GST = $2,500.00 × 15% = $375.00 → $2,875.00 including GST
- If it includes GST: GST = $2,500.00 × 3 / 23 = $326.09 → $2,173.91 excluding GST
GST table
| Amount | If exclusive: total incl. GST | If inclusive: GST inside | If inclusive: excl. GST |
|---|---|---|---|
| Amount: $50.00 | If exclusive: total incl. GST$57.50 | If inclusive: GST inside$6.52 | If inclusive: excl. GST$43.48 |
| Amount: $100.00 | If exclusive: total incl. GST$115.00 | If inclusive: GST inside$13.04 | If inclusive: excl. GST$86.96 |
| Amount: $500.00 | If exclusive: total incl. GST$575.00 | If inclusive: GST inside$65.22 | If inclusive: excl. GST$434.78 |
| Amount: $1,000.00 | If exclusive: total incl. GST$1,150.00 | If inclusive: GST inside$130.43 | If inclusive: excl. GST$869.57 |
| Amount: $5,000.00 | If exclusive: total incl. GST$5,750.00 | If inclusive: GST inside$652.17 | If inclusive: excl. GST$4,347.83 |
| Amount: $10,000.00 | If exclusive: total incl. GST$11,500.00 | If inclusive: GST inside$1,304.35 | If inclusive: excl. GST$8,695.65 |
Frequently asked questions
How do I add GST to a price in New Zealand?
Multiply the GST-exclusive price by 15% and add it, or multiply by 1.15. $100.00 excluding GST carries $15.00 GST, so the GST-inclusive price is $115.00.
How much GST is in a GST-inclusive price?
Three twenty-thirds of it: multiply the inclusive price by 3 and divide by 23. Inland Revenue's example: $100.00 including GST contains $13.04 GST, leaving $86.96 excluding GST. Taking 15% of the inclusive price gives the wrong answer.
What is the GST rate in New Zealand?
15% on most goods and services (Goods and Services Tax Act 1985). The rate has been 15% since 1 October 2010.
What is zero-rated or exempt from GST?
Exports and some land transactions are zero-rated (GST at 0%); residential rent and most financial services are exempt. This calculator assumes a standard-rated supply.
How is rounding handled?
Amounts are rounded to the cent and the GST-exclusive amount plus the GST always equals the GST-inclusive total. On a tax invoice with many lines, totals can differ by a cent depending on whether GST is rounded per line or on the total.
Sources
Assumes a standard-rated supply; zero-rated and exempt supplies are not covered. Results are for guidance only.
GST 15% · Updated: