Skip to content
Free Indian Tools

Tax · Free tool

GST Calculator

Add GST to a base price or extract GST from a tax-inclusive bill — the trick most online calculators get wrong. Shows the CGST + SGST split (intra-state) and the equivalent IGST (inter-state).

Amount is the net (pre-tax) figure. We add GST on top.

₹1,000

Quick presets

Net (pre-tax)
₹1,000
GST @ 18%
₹180
Total bill
₹1,180
CGST @ 9.00%
₹90
SGST @ 9.00%
₹90

How GST is calculated

Adding GST: if the base price is ₹100 and the GST rate is 18%, the GST is ₹18 and the total bill is ₹118. Extracting GST (reverse calculation) is what you do when a restaurant or invoice quotes a tax-inclusive figure: the formula is Net = Total ÷ (1 + rate). So a ₹118 inclusive bill at 18% GST means ₹100 net and ₹18 GST — not ₹118 × 18%.

CGST + SGST vs IGST

Intra-state sales (same state) split GST equally into CGST (Centre) and SGST (State). So 18% GST becomes 9% CGST + 9% SGST. Inter-state sales charge a single IGST that equals the full GST rate. The total tax is identical — only the routing changes.

Common GST rates in India

  • 0% / Exempt: fresh fruits, vegetables, milk, books, healthcare, education.
  • 3%: gold, silver, jewellery (special rate).
  • 5%: packaged staples, restaurant bills (without ITC), economy transport.
  • 12%: butter, cheese, hotel rooms below ₹7,500/night, business-class travel.
  • 18%: most services, mobiles, electronics, premium hotel rooms.
  • 28%: luxury and sin goods — ACs, large TVs, cars, tobacco, aerated drinks.

FAQ

How do I extract GST from a tax-inclusive price?

Use the "Reverse" or "Inclusive" mode. For ₹118 with 18% GST: base = 118 × 100 / 118 = ₹100; GST = ₹18. The calculator handles this both ways.

CGST + SGST or IGST?

Same state transaction (intra-state) → CGST + SGST split (9% + 9% for 18%). Different states (inter-state) → IGST (full 18%). Both add up to the same total.

Are 0%, 5%, 12%, 18%, 28% the only rates?

Yes — five GST slabs. Plus cess on demerit goods (tobacco, luxury cars, soda). Some special rates: 0.25% on diamonds, 3% on gold, 1.5% on jewellery making.