Calculators & ProductivityRuns in your browser

GST Calculator

Add or remove GST with the CGST/SGST breakdown.

Runs in your browserUpdated 2026-11-08 Report a problem

What this gst calculator does

GST Calculator handles both directions of India's Goods and Services Tax. Exclusive mode adds GST to a base amount; inclusive mode works backwards from a price that already contains GST to find the taxable value and the tax component. It also splits the tax into CGST and SGST for intra-state transactions, or shows the full amount as IGST for inter-state supply.

Rates are not hard-coded to one number: choose a common slab or enter any rate. This matters because GST rates vary by goods and services and can change. The calculator performs arithmetic only — it does not decide which rate legally applies to your product.

Why use it

Build an invoice with the correct tax breakdown.
Find the base price hidden inside a tax-inclusive quote.
Check a supplier's GST calculation before approving a bill.

How to use it

1Enter the amount.
2Choose a GST rate or type a custom one.
3Select whether the amount includes GST.
4Choose intra-state (CGST + SGST) or inter-state (IGST) and read the breakdown.

Worked examples

Add 18% GST

Input

₹10,000 exclusive · 18% · intra-state

Output

GST ₹1,800 · CGST ₹900 + SGST ₹900 · total ₹11,800

Remove GST

Input

₹11,800 inclusive · 18%

Output

Taxable value ₹10,000 · GST ₹1,800

Inclusive tax is not 18% of the total; it is 18/118 of it.

Common mistakes

Taking 18% of an inclusive price, which overstates the tax. Divide by 1.18 instead.
Using CGST+SGST on an inter-state invoice; inter-state supply attracts IGST.
Assuming one rate applies to a mixed invoice; each line item can have a different rate.

Frequently asked questions

How do I remove GST from a total?

Divide the inclusive amount by (1 + rate/100). At 18%, ₹11,800 ÷ 1.18 = ₹10,000 taxable value, leaving ₹1,800 tax.

What is the difference between CGST/SGST and IGST?

Intra-state supplies split the tax equally between central and state governments. Inter-state supplies are taxed under IGST, collected by the centre and apportioned to the destination state.

Does this tool tell me which GST rate applies?

No. Rate classification depends on the specific goods or services and current notifications. Use the arithmetic here once you know the correct rate.

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