GST Calculator
Add GST to a base price or strip it out of an inclusive figure, and see the CGST, SGST or IGST split for your invoice.
Common rates
Goods and Services Tax in India
GST is an indirect tax on the supply of goods and services, introduced on 1 July 2017. It replaced a patchwork of central and state levies including VAT, service tax, excise duty, octroi and entry tax. The tax is destination based, meaning revenue accrues to the state where consumption happens rather than where production happens.
Because GST applies at every stage of the supply chain with credit for tax already paid, the eventual burden falls on the final consumer. Businesses in between claim input tax credit on their purchases, so they remit only the tax on the value they add.
The four components
| Component | Stands for | When it applies | Who collects it |
|---|---|---|---|
| CGST | Central GST | Supply within a single state | Central government |
| SGST | State GST | Supply within a single state | That state government |
| IGST | Integrated GST | Supply across state borders, and imports | Centre, later apportioned to the destination state |
| UTGST | Union Territory GST | Supply within a union territory without a legislature | Union territory administration |
For a supply inside one state, an 18% rate splits into 9% CGST and 9% SGST. For an interstate supply the entire 18% is charged as IGST. The total tax is the same either way; only the allocation differs.
Working out GST
Rate slabs and what falls in them
| Rate | Typical items |
|---|---|
| 0% or exempt | Fresh fruit and vegetables, unbranded flour and rice, milk, curd, bread, salt, eggs, newspapers, school education, most healthcare services |
| 5% | Sugar, tea, coffee, edible oil, packaged food, life-saving medicines, footwear under ₹1,000, economy air travel, small restaurants |
| 12% | Butter, ghee, cheese, processed food, fruit juice, mobile phones, umbrellas, business-class air travel, apparel above ₹1,000 |
| 18% | Most goods and services, including IT services, telecom, financial services, restaurants with air conditioning, cement fittings, biscuits, branded garments |
| 28% | Cars, motorcycles above 350cc, aerated drinks, tobacco products, luxury hotel stays, air conditioners, dishwashers, some cosmetics |
A compensation cess applies on top of 28% for certain goods such as cars, tobacco and aerated drinks. Rate classifications are revised periodically by the GST Council, so check the current HSN or SAC code for your specific product or service.
Who must register for GST
- Goods suppliers: aggregate turnover above ₹40,00,000 in most states, and ₹20,00,000 in special category states.
- Service providers: aggregate turnover above ₹20,00,000, and ₹10,00,000 in special category states.
- Interstate suppliers: registration is mandatory regardless of turnover.
- E-commerce sellers and operators: mandatory regardless of turnover.
- Casual and non-resident taxable persons: mandatory before commencing supply.
- Reverse charge liability: anyone required to pay tax under reverse charge must register.
Return filing
| Return | Purpose | Frequency | Typical due date |
|---|---|---|---|
| GSTR-1 | Details of outward supplies | Monthly, or quarterly under QRMP | 11th of the following month |
| GSTR-3B | Summary return with tax payment | Monthly | 20th of the following month |
| GSTR-4 | Return for composition scheme dealers | Annually | 30 April |
| GSTR-9 | Annual return | Annually | 31 December |
| GSTR-9C | Reconciliation statement, where applicable | Annually | 31 December |
Composition scheme. Small businesses with turnover up to ₹1.5 crore can pay a flat rate of 1% for traders and manufacturers, or 5% for restaurants, on turnover instead of the regular slab rates. The trade-off is that they cannot claim input tax credit and cannot make interstate supplies.
Points worth remembering
- Always check whether a quoted price already includes GST before calculating.
- The tax total is identical for intrastate and interstate supply, only the split differs.
- Reverse GST is not simple subtraction. Use the correct divisor of 100 plus the rate.
- Input tax credit is only available if your supplier has actually filed and paid.
- A tax invoice must show the HSN or SAC code, GSTIN of both parties, and the tax split separately.
- Late filing attracts interest at 18% per annum plus a per-day late fee.
Frequently asked questions
India has five main slabs: 0% for exempt items, then 5%, 12%, 18% and 28%. A compensation cess applies on top of 28% for goods such as cars, tobacco and aerated drinks. Most goods and services fall in the 18% band.
For a supply within one state, the tax splits equally into Central GST and State GST, so 18% becomes 9% plus 9%. For a supply across state borders, the entire 18% is charged as Integrated GST. The total tax is identical either way; only the allocation between governments differs.
Divide by 100 plus the rate, then multiply by 100. From a total of 11,800 at 18%, the base is 11,800 x 100 / 118 = 10,000 and the GST is 1,800. Simply subtracting 18% gives the wrong answer.
Goods suppliers with turnover above 40,00,000 in most states, and service providers above 20,00,000. Registration is mandatory regardless of turnover for interstate suppliers, e-commerce sellers and operators, casual taxable persons and anyone liable under reverse charge.
Small businesses with turnover up to 1.5 crore can pay a flat 1% for traders and manufacturers, or 5% for restaurants, on turnover instead of regular slab rates. The trade-off is no input tax credit and no interstate supplies.
GSTR-1 for outward supplies is due by the 11th of the following month, and GSTR-3B with tax payment by the 20th. The annual return GSTR-9 is due by 31 December. Late filing attracts interest at 18% per annum plus a daily late fee.