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GST calculator for inclusive and exclusive prices

Enter an amount and the applicable GST rate. Instantly calculate the tax-exclusive value, tax amount and final payable amount for intra-state or inter-state treatment.

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Calculate an amount

Enter the rate applicable to your product or service; the tool does not determine GST classification.
Choose based on the applicable place-of-supply rules; this tool does not determine place of supply.
Example: When ₹1,180 includes 18% GST, the taxable value is ₹1,000 and the GST portion is ₹180 (before possible rounding differences).

Your GST breakdown

Total payable
₹1,180.00
Taxable value₹1,000.00
GST amount₹180.00
CGST₹90.00
SGST₹90.00
IGST₹0.00

CGST + SGST split

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Values are rounded to two decimal places. Actual tax invoices may need line-level rounding and statutory validations.

GST-inclusive versus GST-exclusive calculation

When an amount already includes GST

For an illustrative GST rate of 18%, divide the total by 1.18 to find the taxable value. With ₹1,180 as the tax-inclusive total, the taxable amount is ₹1,000 and the included tax is ₹180. The tool does this reverse calculation automatically.

When GST must be added

Multiply the taxable amount by the applicable rate and add the resulting tax. At an illustrative 18% rate on ₹1,000, GST is ₹180 and the total is ₹1,180.

CGST + SGST or IGST?

Choose the supply category appropriate for the transaction. For the selected intra-state option this calculator divides total GST into CGST and SGST; for the selected inter-state option it displays IGST instead. Applicable place-of-supply rules, exemptions, GST rates and invoice requirements need separate review.

Next steps for your business

See our GST invoice checklist, GST billing features and free invoice maker. For primary guidance, refer to CBIC invoice rules. This is a calculation aid, not tax advice.