Finance
GST Calculator
Convert between net and gross prices without touching a spreadsheet. Pick whether you’re adding GST to a base amount or stripping it out of a tax-inclusive total.
Add GST to a base price or strip it from a tax-inclusive figure in one step.
GST relationships
Gross = Net × (1 + rate) Net = Gross ÷ (1 + rate) GST = Gross − Net
Rate is expressed as a decimal (e.g., 10% = 0.10). The same formulas handle GST or VAT-style taxes where a single percentage applies to the taxable amount.
How to use
- Enter the amount you know (net or gross).
- Provide the GST rate for your region.
- Choose whether to add GST or remove it, then read net, tax, and gross outputs.
Example
Input: Amount = $120 (net), GST rate = 10%, Mode = Add
Output: GST = $12, Gross = $132
Student-friendly breakdown
This walkthrough emphasizes the most searched ideas for GST Calculator: gst calculator, gst inclusive calculator, gst exclusive calculator, gst amount calculator. Start with the formula above, then follow the guided steps to double-check your work. For quick revision, highlight the givens, plug into the equation, and finish by verifying your units.
Need more support? Use the links below to open the long-form guide, browse additional examples, or hop into adjacent calculators within the same topic — each one is a quick way to double-check your work or handle a related question without starting from scratch.
Deep dive & study plan
GST Calculator: Adds or removes Goods and Services Tax from any amount. It's built around gst, tax inclusive, tax exclusive, so you can go from a raw question to a checked answer without switching tools.
The math behind it: Rate is expressed as a decimal (e.g., 10% = 0.10). The same formulas handle GST or VAT-style taxes where a single percentage applies to the taxable amount. The core relationship is Gross = Net × (1 + rate) Net = Gross ÷ (1 + rate) GST = Gross − Net, shown above the calculator so you can see exactly how your inputs turn into the result.
To use it well: (1) Enter the amount you know (net or gross). (2) Provide the GST rate for your region. (3) Choose whether to add GST or remove it, then read net, tax, and gross outputs. Keep your units consistent as you go, and re-run a case you already know the answer to — it's the fastest way to catch a typo before it throws off a result you're relying on.
Worked example: entering Amount = $120 (net), GST rate = 10%, Mode = Add returns GST = $12, Gross = $132. Try swapping in your own numbers next, especially a case you're unsure about, before you use this for something that matters.
Quick retention checklist
- Speak the formula aloud (or annotate it) so the relationships stick.
- Write each step in your own words and compare with the numbered list above.
- Swap in new numbers for the Example to make sure the calculator (and your logic) handles edge cases.
- Check at least one related calculator below — it's the fastest way to confirm your numbers still line up from a different angle.
FAQ & notes
Does it support multiple GST tiers?
It focuses on a single rate at a time. Run the calculation separately for each tier if your invoice mixes taxable and non-taxable items.
Can I change currencies?
Yes. The math is percentage based, so simply enter figures in your preferred currency and read the results in the same unit.
What formula does the GST Calculator use?
Rate is expressed as a decimal (e.g., 10% = 0.10). The same formulas handle GST or VAT-style taxes where a single percentage applies to the taxable amount.
How do I use the GST Calculator?
Enter the amount you know (net or gross). Provide the GST rate for your region. Choose whether to add GST or remove it, then read net, tax, and gross outputs.