This free GST calculator for India handles both directions of the most common tax task: adding GST to a base price, or removing it from a GST-inclusive price. Pick a rate (5%, 12%, 18%, 28%, or a custom value), choose exclusive or inclusive, and see the base amount, GST, and total instantly — with an optional CGST/SGST/IGST split. Everything runs in your browser; nothing is stored or sent anywhere.
How to use this calculator
- Enter the amount — either your base price (exclusive) or your final GST-inclusive price.
- Choose the GST rate — tap 5, 12, 18, or 28%, or enter a custom rate.
- Pick exclusive or inclusive — exclusive adds GST on top; inclusive backs it out of the price.
- Optionally round to the nearest rupee, and toggle the split to see CGST/SGST or IGST.
- Exclusive (add GST):
GST = Amount × rate%, Total = Amount + GST.
- Inclusive (remove GST):
Base = Amount ÷ (1 + rate%), GST = Amount − Base.
- Intra-state split:
CGST = SGST = GST ÷ 2.
- Inter-state:
IGST = full GST.
GST rates & the split
India's common GST slabs are 5%, 12%, 18%, and 28%, with the right rate depending on the product category (its HSN code). For a sale within the same state (intra-state), the GST is split equally into CGST and SGST. For a sale across state lines (inter-state), the whole amount is charged as IGST. The split here is informational — it helps you see the breakdown, but always confirm the correct rate for your specific product.
Worked example
Base amount ₹1,000 · GST 18% · Exclusive
GST = 1,000 × 18% = ₹180. Total = 1,000 + 180 = ₹1,180.
Intra-state split: CGST ₹90 + SGST ₹90. Inter-state: IGST ₹180.
Tips & edge cases
- Use inclusive mode when your displayed price already includes GST and you need the tax portion for invoicing.
- Confirm your HSN rate — categories sometimes shift slabs; this tool doesn't assume a rate for you.
- Rounding can create a small round-off line on invoices; the toggle shows it explicitly.
- Marketplace fees may attract their own GST — this calculator is for the product amount, not platform charges.
Glossary
- GST: Goods and Services Tax, India's unified indirect tax.
- Exclusive: the amount is the base; GST is added on top.
- Inclusive: the amount already contains GST; the base is backed out.
- CGST / SGST: the two halves of GST on an intra-state sale (central and state).
- IGST: the integrated GST charged on an inter-state sale.
FAQs
What's the difference between exclusive and inclusive GST?
Exclusive means your amount is the base price and GST is added on top to reach the total. Inclusive means your amount already contains GST, so the tool works backwards to find the base and the tax portion.
When is GST split into CGST and SGST versus IGST?
For a sale within the same state (intra-state), GST is split equally into CGST and SGST. For a sale across state lines (inter-state), the full amount is charged as a single IGST.
Which GST rate should I use?
It depends on your product's category and HSN code — common slabs are 5%, 12%, 18%, and 28%. This tool doesn't assume a rate; confirm the correct one for your specific product.
Why does the rounding toggle matter?
GST amounts often aren't whole rupees. Rounding to the nearest rupee creates a small round-off figure that appears on many invoices, and the toggle shows it explicitly so your numbers reconcile.
Is this official tax advice?
No. This is a free calculation tool for convenience. For filing, compliance, and the correct rate for your products, consult a qualified tax professional or the official GST portal.
Is my data saved anywhere?
No. Everything is calculated in your browser — nothing you type is uploaded or stored on any server.
