How much GST is charged on Rs 1 lakh?
GST is added on top of the taxable value, not carved out of it, so the number to add is straightforward — the part people get wrong is the split between CGST, SGST and IGST.
GST on Rs 1,00,000 at the standard 18% rate is Rs 18,000, making the invoice total Rs 1,18,000. At 5% it is Rs 5,000, at 12% Rs 12,000 and at 28% Rs 28,000. On an intra-state supply the 18% splits into CGST Rs 9,000 and SGST Rs 9,000; on an inter-state supply the whole Rs 18,000 is IGST.
Worked out 2026-09-10 (IST) · GST added on a taxable value of Rs 1,00,000GST on Rs 1,00,000 at every rate
| Rate | GST amount | Invoice total | CGST | SGST | IGST |
|---|---|---|---|---|---|
| 0.25% | 250.00 | 1,00,250.00 | 125.00 | 125.00 | 250.00 |
| 3% | 3,000.00 | 1,03,000.00 | 1,500.00 | 1,500.00 | 3,000.00 |
| 5% | 5,000.00 | 1,05,000.00 | 2,500.00 | 2,500.00 | 5,000.00 |
| 12% | 12,000.00 | 1,12,000.00 | 6,000.00 | 6,000.00 | 12,000.00 |
| 18% | 18,000.00 | 1,18,000.00 | 9,000.00 | 9,000.00 | 18,000.00 |
| 28% | 28,000.00 | 1,28,000.00 | 14,000.00 | 14,000.00 | 28,000.00 |
The same rates on other amounts
| Taxable value | GST at 5% | at 12% | at 18% | at 28% | Total at 18% |
|---|---|---|---|---|---|
| 1,000 | 50 | 120 | 180 | 280 | 1,180 |
| 5,000 | 250 | 600 | 900 | 1,400 | 5,900 |
| 10,000 | 500 | 1,200 | 1,800 | 2,800 | 11,800 |
| 25,000 | 1,250 | 3,000 | 4,500 | 7,000 | 29,500 |
| 50,000 | 2,500 | 6,000 | 9,000 | 14,000 | 59,000 |
| 1,00,000 | 5,000 | 12,000 | 18,000 | 28,000 | 1,18,000 |
| 5,00,000 | 25,000 | 60,000 | 90,000 | 1,40,000 | 5,90,000 |
| 10,00,000 | 50,000 | 1,20,000 | 1,80,000 | 2,80,000 | 11,80,000 |
The formula
GST to add = taxable value × rate ÷ 100
invoice total = taxable value × (1 + rate ÷ 100)
intra-state split: CGST = SGST = GST ÷ 2
Check your own numbers
Enter any amount and rate, add or remove GST, and see the CGST/SGST/IGST split.
Frequently asked
Is GST added to the price or included in it?
It depends on how the price was quoted. A price described as "exclusive of GST" or "plus taxes" has GST added on top, so Rs 1,00,000 becomes Rs 1,18,000. A price described as "inclusive of all taxes" already contains it, so Rs 1,00,000 inclusive at 18 per cent is Rs 84,745.76 of value plus Rs 15,254.24 of GST. Under the Legal Metrology rules the MRP on a packaged product is always inclusive.
What is the difference between CGST, SGST and IGST?
They are the same total tax split three ways depending on where the supply goes. Within one state, the rate is halved between CGST (to the Centre) and SGST (to the state) - 18 per cent becomes 9 plus 9. Across state lines, the whole rate is charged as IGST, which the Centre then apportions. Union territories without a legislature use UTGST in place of SGST. The buyer pays the same either way.
Which rate applies to my invoice?
It is set by the HSN or SAC code of what you are selling, not by the amount. Most services, including software, consulting and professional fees, are at 18 per cent. Restaurants are usually 5 per cent without input credit. Packaged foods sit at 5 or 12, and cars, tobacco and aerated drinks at 28 plus cess. Check the current rate notification for your HSN code before invoicing - the schedules do get amended.
Do I need to charge GST if my turnover is small?
Registration is compulsory above Rs 40 lakh of turnover for goods and Rs 20 lakh for services in most states, with lower thresholds of Rs 20 lakh and Rs 10 lakh in the special-category states. Below the threshold you may register voluntarily, which lets you claim input credit but also obliges you to file returns. Inter-state supply of goods requires registration regardless of turnover.
Related answers
Want this calculator on your own site?
We build the same calculators — EMI, tax, SIP, BMI — as embeddable widgets in your branding, wired to your lead form. Tell us which one and we will send a working demo.
Request received
Thanks — we will reply within one business day. Meanwhile, all 164 tools are free to use, no signup.