GST Calculator
Add or remove GST at any rate and see the CGST/SGST split.
1,000
Net (before tax)
180
GST amount
1,180
Gross (after tax)
Tax breakdown
| CGST (9%) — intra-state | 90 |
| SGST (9%) — intra-state | 90 |
| IGST (18%) — inter-state | 180 |
Formula used: GST = net × rate ÷ 100; gross = net + GST
About GST Calculator
Goods and Services Tax is charged as a percentage of the taxable value, and the everyday confusion is whether a quoted price already includes it.
This calculator works in both directions - adding tax to a net price or extracting it from a gross price - and breaks the result into CGST, SGST or IGST for invoicing.
How GST Calculator works in your browser
Adding GST multiplies the net amount by (1 + rate ÷ 100). Removing it divides the inclusive price by the same factor, and the difference between the two prices is the tax component. For intra-state supply the tax is split equally into CGST and SGST; for inter-state supply the whole amount is shown as IGST.
The standard slabs of 0, 5, 12, 18 and 28 percent are available alongside a custom rate, so the calculator still works if rates change or you are checking an older invoice.
When to use it
- Working out the pre-tax value of a GST-inclusive price quoted by a supplier.
- Preparing an invoice that needs the CGST and SGST amounts shown separately.
- Checking that a bill has applied the right slab to the right amount.
Frequently asked questions
How do I remove GST from a price?
Divide the inclusive price by (1 + rate/100). At 18 percent, divide by 1.18; the difference between the two figures is the tax.
What is the difference between CGST, SGST and IGST?
Intra-state supply splits the tax equally into CGST and SGST. Inter-state supply uses a single IGST at the full rate.
What is the reverse GST formula?
To strip tax from an inclusive price, divide by (1 + rate/100). The difference is the tax component.
How is CGST and SGST split?
For intra-state supply the total is split equally between central and state GST. Inter-state supply uses a single IGST at the full rate.
Which rates are supported?
The standard slabs of 0, 5, 12, 18 and 28 percent, plus any custom rate you enter.