How to use this 15% gst calculator
- Enter the amount in $.
- Choose whether the amount is inclusive or exclusive of GST.
- Select the GST rate (fixed at 15%), then click Calculate.
- Review the receipt-style breakdown on the right, then use Clear to reset.
What is GST at a fixed percentage rate?
New Zealand's standard GST is 15%, and several jurisdictions use 15% as a headline VAT/GST rate. Enter any amount to split tax-inclusive and tax-exclusive prices.
Forward and reverse formulas
When you know the price excluding tax:
When you know the tax-inclusive price, work backward:
Example at 15%
If the price excluding GST is $1,000, tax is $150.00 and the price including tax is $1,150.00.
GST vs sales tax vs VAT
Goods and services tax (GST) and value-added tax (VAT) are multi-stage consumption taxes with input-tax credits for registered businesses. Sales tax (common in the United States) is typically charged once at retail. This calculator focuses on single-rate GST/VAT math — verify exemptions and filing rules with your local revenue authority.
More GST calculators
Explore country-specific and rate-specific GST tools, or read the full GST calculator guide for formulas and jurisdiction notes.
- By country
- By rate ($)
Also see our Sales Tax Calculator for U.S. state and local rates.