Even with a calculator close to hand, a few shortcuts to help you calculate Goods and Services Tax (GST) are real handy. The whole business of dividing by 11 or multiplying by 0.15 can get very ugly indeed.
| Australia | New Zealand | |
|---|---|---|
| To calculate how much GST to add | Multiply by 0.1 | Multiply by 0.15 |
| To add GST to arrive at a total price | Multiply by 1.1 | Multiply by 1.15 |
| To calculate how much GST is included in a price | Divide by 11 | Multiply by 3 and then divide by 23 |
| To calculate how much the price was before GST | Divide by 1.1 | Divide by 1.15 |