VAT and Sales Tax Calculator
Add or remove VAT, GST or sales tax at any rate, in both directions.
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GST Calculator
Add or remove GST, with the CGST and SGST split.
GST Calculator tool
Common rates are 5, 12, 18 and 28.
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GST
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Net amount
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Gross amount
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CGST
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SGST
| Rate | Net | GST | Gross |
|---|
Taking 18% off a gross price is not the same as adding 18% to a net one. Removing GST divides by 1.18; subtracting 18% of the gross takes off too much, which is the commonest mistake in reverse tax arithmetic.
About the GST Calculator
GST Calculator adds goods and services tax to a net amount or takes it out of a gross one, at whatever rate applies. Both directions are needed in practice: you add GST when pricing and invoicing, and remove it when working out the taxable value behind a total you have been charged.
Removing GST is where mistakes happen. A gross amount of 1,180 at 18 per cent contains 180 of tax, not 212.40, because the tax was charged on the net figure of 1,000. Subtracting 18 per cent from the gross takes off too much; the correct operation is dividing by 1.18. The page says which it did, in those terms.
The CGST and SGST split is offered because Indian GST divides the tax between central and state government for a sale inside one state, each taking half the rate, while an inter-state sale is charged as a single IGST. The split is presentational -- the total tax is identical -- but it is what an invoice has to show.
This is arithmetic, not financial advice. It tells you what the numbers do; it cannot tell you whether a decision is right for your circumstances. Fees, taxes and local rules vary, so check anything that matters against the actual offer and speak to someone qualified before committing.
Everything is worked out inside your browser. Nothing you enter is uploaded, logged or stored, which matters for the financial calculators in particular: the figures you put into them are nobody else's business.
Looking for something this does not cover? FreeToolsZone.org is more free browser-based tools, organised by job, and it is worth a look if gst calculator is only part of what you are working on.
How to use the GST Calculator
- Choose what do you need and split the taxThe fields below change to match what you pick, so only the figures that matter to your case are asked for.
- Enter amount and gst rate (%)Decimals are fine, and thousands separators are accepted and ignored.
- Read the gst, net amount and gross amountThe figures update as you type. The Calculate button is there if you would rather press something, but nothing waits for it.
- Copy or check the resultCopy the summary with the copy button, or open the table to check it row by row.
Features
- Shows gst, net amount, gross amount, cgst and sgst together, so you are not running it twice
- A results table you can read across
- Updates as you type, with no button to press and no page reload
- Copy the result in one click
- Free, no sign-up, and it runs entirely in your browser
Who uses this tool
The gst calculator is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:
- Adding GST to a quote or an invoice
- Working out the taxable value behind a gross total
- Splitting GST into CGST and SGST for an invoice
- Comparing the effect of different GST slabs
Frequently asked questions
How do I remove GST from a total?
Divide by one plus the rate as a decimal. At 18 per cent, divide by 1.18. Do not subtract 18 per cent of the gross amount.
What is the CGST and SGST split?
For a sale within one Indian state, GST is split equally between central and state government. An 18 per cent rate becomes 9 per cent CGST and 9 per cent SGST.
Is this the same as VAT?
The arithmetic is identical. Use the VAT calculator if that is the name where you are; the only difference here is the CGST and SGST split.
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If the gst calculator is not quite what you need, these other free tools solve closely related problems, and there are 19 more in business calculators.
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Checked and rebuilt on 2026-10-14. The method this calculator uses is described in the section above, and corrections go through the contact page.