What it calculates
GST is charged on the taxable value of a supply. Within a state it is split equally between Central GST (CGST) and State/UT GST; between states it is charged as Integrated GST (IGST).
How it works
Exclusive: tax = amount × rate. Inclusive: taxable value = amount ÷ (1 + rate), and tax is the difference.
Formula
GST = Taxable value × Rate ÷ 100; Taxable value = Inclusive amount ÷ (1 + Rate ÷ 100)
- Intra-state: CGST = SGST = GST ÷ 2
- Inter-state: IGST = GST
How to use it
- Enter the amount.
- Choose the GST rate for your goods or service.
- Say whether the amount already includes GST.
- Choose whether the supply is within your state or to another state.
For ₹10,000 before GST at 18% within the same state:
Why it helps
- Quick price quotes with tax.
- Checks the tax inside an inclusive bill.
Limitations
- The correct rate depends on the HSN/SAC classification and exemptions; this tool does not decide it.
- Compensation cess, reverse charge and composition-scheme rules are not modelled.
Frequently asked questions
When is IGST charged instead of CGST + SGST?
When the supplier’s location and the place of supply are in different states (or a supply is to or from a Special Economic Zone or an export).
Can I claim the GST I pay on purchases?
A registered business can usually claim input tax credit on purchases used for its taxable business, subject to the conditions in the CGST Act (valid invoice, goods or services received, supplier filed returns). Some items are blocked.
Sources
- GST rate rationalisation effective 22 September 2025 (e.g. Notification No. 9/2025-Central Tax (Rate), 17 Sep 2025) — checked via published summaries; confirm on cbic-gst.gov.in — CBIC (checked 2026-10-09)
Estimates for planning only; not tax advice. The rate notified for your HSN/SAC code and the place-of-supply rules decide the actual tax.