GST Calculator
Add or remove GST from any amount across all Indian tax slabs.
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GST Calculator
Use the formula and worked example below to calculate manually.
Overview
The GST calculator lets you instantly add GST to a base price (exclusive → inclusive) or remove GST from a final price to find the base amount (inclusive → exclusive), for any GST slab — 5%, 12%, 18%, or 28%.
How to use this calculator
- Enter the amount.
- Select whether the amount is GST-exclusive (before tax) or GST-inclusive (after tax).
- Choose the applicable GST rate: 5%, 12%, 18%, or 28%.
- The calculator shows GST amount, CGST, SGST (or IGST for inter-state), and the final price.
Understanding the inputs & results
GST-exclusive (base price)
The price before GST is added. GST is calculated on this amount.
GST-inclusive (final price)
The price after GST has been added. Use 'remove GST' mode to find the base price.
CGST
Central GST — half the GST rate, collected by the central government on intra-state supplies.
SGST
State GST — the other half, collected by the state government on intra-state supplies.
IGST
Integrated GST — the full GST rate, collected by the central government on inter-state supplies.
GST slabs
GST is levied at 5%, 12%, 18%, or 28% depending on the category of goods or services.
The formula
GST formulas
Inclusive → GST Amount = Price / (1 + rate) × rate | Exclusive → GST Amount = Price × rate
For exclusive prices, multiply by the GST rate. For inclusive prices, divide by (1 + rate) to get the base, then the difference is GST.
Worked example
Base price ₹10,000 at 18% GST (intra-state).
- GST = 10,000 × 0.18 = ₹1,800.
- CGST = ₹900, SGST = ₹900.
- Final price = ₹11,800.
✓ GST of ₹1,800 (₹900 CGST + ₹900 SGST). Final price = ₹11,800.
Frequently asked questions
GST rates are subject to change by the GST Council. Verify the applicable rate for your specific goods or service category before raising an invoice.