GST Calculator
Add GST to an amount, or pull it out of a GST-inclusive price. Same-state supply splits into CGST + SGST; a different-state supply is all IGST.
A quick calculation, not tax advice. Confirm the correct rate and place of supply for your goods or services.
This calculator just splits the tax — the app creates the actual GST invoice, tracks who's paid, and keeps every filing period's numbers ready to export.
How it works
GST is a percentage of the taxable value. Adding it: total = amount × (1 + rate). Removing it from an inclusive price: base = amount ÷ (1 + rate). For a supply within one state the GST is split into two equal halves — CGST to the centre and SGST to the state. For an inter-state supply the whole GST is IGST.
An example
A ₹10,000 invoice at 18% GST, same state. GST is ₹1,800 — ₹900 CGST + ₹900 SGST. The invoice total is ₹11,800. If the client were in another state, it would be ₹1,800 IGST instead.
Common questions
How do I remove GST from an inclusive price?
Divide by (1 + rate). A ₹1,180 price that includes 18% GST is ₹1,000 base + ₹180 GST. Switch the mode to "GST-inclusive".
CGST, SGST or IGST — which one?
Same-state supply: CGST + SGST, split equally. Different-state supply: IGST for the full amount. The place of supply decides.
Which rate applies to me?
It depends on your HSN/SAC code. Many services are 18%; goods span 0/5/12/18/28%. Check the notified rate for your item, then this does the maths.