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Free GST Calculator
Add GST to an amount, or remove GST from an inclusive price — with the CGST/SGST or IGST split worked out for you. Instant, and nothing to install.
How GST is calculated
Adding GST (the amount is before tax): GST = amount × rate ÷ 100, and the total = amount + GST. For ₹10,000 at 18%, GST is ₹1,800 and the total is ₹11,800.
Removing GST (the amount already includes tax): taxable value = amount ÷ (1 + rate ÷ 100), and GST = amount − taxable value. From an ₹11,800 GST-inclusive price at 18%, the taxable value is ₹10,000 and GST is ₹1,800.
CGST/SGST vs IGST: if buyer and seller are in the same state, the GST splits equally into CGST and SGST. If they're in different states, the whole amount is IGST. New to this? Read CGST vs SGST vs IGST explained.
From calculation to invoice
Once the numbers are right, turn them into a GST-ready PDF invoice — free, no sign-up — or open a free account to save your customers and get paid over WhatsApp.