GST calculator
Add GST to a price, or find the GST already inside one, split the way an invoice needs it.
Which slab your goods fall in is set by their HSN code — check yours if you are unsure.
Type an amount above and the split appears here.
What this is for
Two jobs. If you know what you want to earn on an item, the first mode adds GST on top and tells you the price to put on the label. If a customer has already paid you a round number — ₹1,500 all-in — the second mode tells you how much of that was tax, which is the figure your invoice and your return need.
The second one is where hand calculation usually goes wrong. Taking 18% of ₹1,500 gives ₹270, but the tax inside ₹1,500 at 18% is ₹228.81: the tax was charged on the price before GST, not on the total. This page works backwards properly, so the taxable value and the tax always add up to exactly what you were paid.
Same-state sales split the tax in half — CGST to the centre, SGST to your state. A sale to another state is one IGST line at the full rate. Which slab applies to what you sell depends on the HSN code of the goods; this page does not guess it for you, you pick the rate.