BillmanGST calculator
Add or remove GST from any amount. Get the taxable value, GST and the CGST/SGST or IGST split — free, no sign-up.
Other rates: 3% (gold & silver), 0.25% (rough diamonds), 1.5% — type any rate.
Adding GST
GST = Amount × Rate ÷ 100. Total = Amount + GST.
₹1,000 × 18% = ₹180 → ₹1,180Removing GST
Taxable value = Amount × 100 ÷ (100 + Rate).
₹1,180 × 100 ÷ 118 = ₹1,000Rules and rates as of October 2026. Always verify on gst.gov.in / cbic-gst.gov.in.
Billman does this on every bill
GST, CGST/SGST/IGST, e-way bills and GSTR-1 — automatically, even offline.
GST calculator FAQ
How do I calculate GST on an amount?
Multiply the amount by the GST rate and divide by 100. For ₹1,000 at 18%, GST is ₹180 and the total is ₹1,180.
How do I remove GST from a price that includes GST?
Divide the price by (100 + GST rate) and multiply by 100. For ₹1,180 including 18% GST, the taxable value is ₹1,000 and GST is ₹180.
When is GST split into CGST and SGST?
When the seller and buyer are in the same state, GST is split equally into CGST and SGST. For a sale to another state, the full GST is charged as IGST.
What GST rates are used in India?
Since GST 2.0 (22 September 2025) the main rates are 5% and 18%, with 40% for luxury and sin goods and 0% for essentials; 12% and 28% remain for a few items. Special rates include 3% for gold and silver and 0.25% for rough diamonds. Check your item’s rate on cbic-gst.gov.in.