How to Calculate GST
Goods and Services Tax (GST) is an indirect tax levied on most goods and services sold in India. Our calculator works two ways:
Add GST: GST = Amount × Rate ÷ 100 | Total = Amount + GST
Remove GST: Base = Amount ÷ (1 + Rate ÷ 100) | GST = Amount − Base
CGST, SGST and IGST
How the GST is split depends on whether the supply is within a state or across states:
| Type of Supply | Tax Charged |
|---|---|
| Intra-state (same state) | CGST + SGST (each half of the GST) |
| Inter-state (different states) | IGST (full GST amount) |
GST Rate Slabs in India
- 0% — essential items (fresh produce, milk, etc.)
- 3% — gold and silver
- 5% — household necessities, transport
- 12% & 18% — most goods and services (18% is the most common)
- 28% — luxury and "sin" goods
Frequently Asked Questions
Is this GST calculator free?
Yes — it's completely free, works on any device, and your figures never leave your browser.
Can I use it for invoices?
Yes. Use "Add GST" for a net price to get the GST and total, then read the CGST/SGST or IGST split for your invoice.