GST Calculator — Add or Remove GST (5%, 12%, 18%, 28%)

Add or remove GST at 5/12/18/28% in one click.

This is the base amount (before GST).

GST rate
Mode

Results

Base amount
₹10,000.00
GST amount (18%)
₹1,800.00
Total amount
₹11,800.00

CGST / SGST split

CGST (½ GST)

₹900.00

SGST (½ GST)

₹900.00

For intra-state sales GST is split evenly into CGST and SGST. For inter-state sales the same total is charged as IGST.

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Calculating GST for every PO and quote is busywork. Procupy auto-applies GST to invoices, splits CGST/SGST/IGST by vendor state, and keeps an audit-ready record of every line item.

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How to use this GST calculator

  1. Enter the amount in rupees. Use the base price if you want to add GST, or the final price if you want to extract GST from a GST-inclusive total.
  2. Pick a GST rate — 5%, 12%, 18%, or 28% — or use the custom field for non-standard slabs.
  3. Choose Add GST or Remove GST. The results panel shows the base, GST, total, and the CGST/SGST split instantly.

GST formula

The three formulas this calculator uses:

  • GST = Base × (Rate/100)
  • Total (GST inclusive) = Base × (1 + Rate/100)
  • Base (from inclusive) = Total / (1 + Rate/100)

CGST and SGST are each half of the total GST amount for intra-state sales. For inter-state sales the same total is levied as IGST instead.

GST rates in India

  • 0% — essentials such as fresh produce, milk, and unbranded food grains.
  • 5% — common household goods, packaged staples, and many transport services.
  • 12% — processed food, business-class travel, and select consumer items.
  • 18% — the standard rate covering most services, IT, and a wide range of goods.
  • 28% — electronics, luxury goods, automobiles, and sin items (often with an additional cess).

Frequently asked questions

How do I calculate GST on an amount?

Multiply the base amount by the GST rate divided by 100. For example, GST on ₹10,000 at 18% is 10,000 × 0.18 = ₹1,800, and the GST-inclusive total is ₹11,800. This calculator does it for you instantly and also splits the tax into CGST and SGST.

What's the difference between CGST, SGST, and IGST?

For intra-state transactions GST is split equally between the Central GST (CGST) and the State GST (SGST) — so 18% becomes 9% CGST + 9% SGST. For inter-state transactions the same total rate is charged as Integrated GST (IGST), which the centre later apportions to the destination state.

Is GST included in MRP?

Yes. Under Indian law the Maximum Retail Price printed on packaged goods is the final price to the consumer and is inclusive of all taxes, including GST. To back-calculate the base price, use this calculator in 'Remove GST' mode with the applicable rate.

How do I calculate GST in reverse (when the amount is GST-inclusive)?

Divide the inclusive total by (1 + Rate/100). For example, ₹11,800 at 18% gives a base of 11,800 / 1.18 = ₹10,000, and the GST component is ₹1,800. Switch this tool to 'Remove GST from amount' mode to do this in one click.

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