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GST Calculator

Calculate GST instantly

Enter amount and select GST slab.

GST Rate

Total Invoice Amount

₹1,180.00

Base ₹1,000.00 + GST ₹180.00

GST Amount

₹180.00

GST Rate

18%

CGST

₹90.00

SGST

₹90.00

Invoice Breakdown

Base amount₹1,000.00
CGST @ 9%₹90.00
SGST @ 9%₹90.00
Total₹1,180.00
🧾 Tax tool

Calculate GST amount
instantly.

Enter the base amount and GST rate to instantly get the GST amount and total invoice value. Works for all GST slabs — 5%, 12%, 18%, and 28%.

GST amountTotal invoice valueAll GST slabsBuyers & sellersFree & instant

Step by step

How to use the GST Calculator

1

Enter base amount

Type the pre-GST price or base invoice amount.

2

Select GST rate

Enter the applicable GST rate — 5, 12, 18, or 28 percent.

3

Get GST amount

Instantly see the GST amount (tax) and the total invoice value including GST.

4

Use for invoicing

Copy the values into your invoice, bill, or receipt for GST compliance.

Why use this calculator?

🏪

Business invoicing

Quickly calculate the GST to add on top of your service or product price before raising a GST-compliant invoice.

🛒

Buyer price check

Verify the GST added to your purchase before paying to ensure the seller is charging the correct slab rate.

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Freelancers & consultants

Freelancers registered under GST must charge 18% GST on services. Use this calculator to quote the right total amount to clients.

How GST is calculated — formula and example

GST (Goods and Services Tax) replaced a complex web of central and state taxes in India in 2017 with a unified destination-based tax. For consumers, it simplified prices. For businesses, it introduced Input Tax Credit (ITC) — the ability to deduct GST paid on purchases from GST collected on sales. This means GST is not a cost to GST-registered businesses who can claim ITC; it is only a final cost to the end consumer.

The four main GST slabs correspond to different types of goods and services. 5% applies to essential items like unbranded food, economy hotel rooms, and transport services. 12% covers processed foods, computers, and some medicines. 18% is the most common rate and applies to most services including software, consulting, telecom, and most manufactured goods. 28% is reserved for luxury goods, tobacco, automobiles, and items considered demerit goods. Zero-rated items include exports and most basic food grains.

For freelancers and small businesses, GST registration is mandatory once turnover exceeds ₹20 lakh per year for services (₹40 lakh for goods, ₹10 lakh in special states). Below this threshold, registration is voluntary. Once registered, you must charge GST on all invoices, file monthly or quarterly returns, and deposit collected GST with the government. The Composition Scheme allows businesses below ₹1.5 crore turnover to pay a flat tax rate without ITC, simplifying compliance for small traders.

Formula

GST Amount = Base Amount × (GST Rate / 100) | Total = Base + GST Amount

Base Amount is the pre-tax price of the goods or service. GST Rate is the applicable slab (5%, 12%, 18%, or 28%). To reverse-calculate the base from a GST-inclusive price: Base = Inclusive Price ÷ (1 + GST Rate / 100).

Worked example

A freelance developer raises an invoice of ₹50,000 for services. GST at 18% applies. GST amount = 50,000 × 18/100 = ₹9,000. Total invoice = ₹59,000. The client pays ₹59,000 and can claim the ₹9,000 as input tax credit if they are GST registered. The developer must deposit ₹9,000 with the government when filing GSTR-1 and GSTR-3B.

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What is GST?

The Goods and Services Tax (GST) is a unified indirect tax levied on the supply of goods and services across India. It came into effect on 1 July 2017 after the Constitution (One Hundred and First Amendment) Act was passed, replacing a fragmented system of central and state levies that included Central Excise Duty, Service Tax, VAT, Entry Tax, and Octroi, among others.

GST is a destination-based tax — it is collected at the point of consumption rather than the point of production. This means the state where the goods or services are finally consumed receives the tax revenue, not the state where they were manufactured. Every business with a turnover above the prescribed threshold must obtain a GST Identification Number (GSTIN) and collect GST on behalf of the government.

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Effective Date

1 July 2017 — replacing over a dozen central and state indirect taxes with a single unified framework.

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Governing Body

The GST Council, chaired by the Union Finance Minister, decides rates, exemptions, and policy changes.

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GSTIN

Every registered business gets a 15-digit GST Identification Number used on all invoices and filings.

GST Rate Slabs — What Falls Where

India uses a multi-tier GST structure with four primary rate slabs. The rate applicable to a specific good or service is determined by its HSN (Harmonised System of Nomenclature) code for goods or SAC (Services Accounting Code) for services.

GST RateCategoryExamples
0% (Exempt)Essential goods & exportsFresh fruits, vegetables, milk, eggs, bread, books, exports
5%Basic necessities & economy servicesPackaged food, economy hotels, transport, life-saving drugs
12%Standard goods & processed itemsProcessed foods, computers, mobile phones, business class air travel
18%Most goods & servicesSoftware, consulting, telecom, restaurants, most manufactured goods
28%Luxury & demerit goodsLuxury cars, tobacco, aerated drinks, casinos, high-end appliances

Cess on top of 28%

Certain goods in the 28% slab — such as luxury cars, tobacco products, and aerated drinks — attract an additional Compensation Cess over and above the 28% GST. This cess was introduced to compensate states for revenue loss during the GST transition period.

CGST, SGST, and IGST — How GST is Split

GST is not a single payment to one authority. Depending on whether a transaction is within a state or across state borders, the tax is divided differently between the central and state governments.

Tax TypeFull FormWhen AppliedSplit
CGSTCentral GSTIntra-state supply (within same state)50% of total GST → Central Govt
SGSTState GSTIntra-state supply (within same state)50% of total GST → State Govt
IGSTIntegrated GSTInter-state supply (across state borders)Full GST rate → Central Govt, then shared
UTGSTUnion Territory GSTSupply within a Union TerritoryReplaces SGST for UTs without legislature

Practical example

A Mumbai-based agency invoices a Mumbai client ₹1,00,000 for services at 18% GST. The invoice shows CGST 9% (₹9,000) + SGST 9% (₹9,000) = ₹18,000 total GST. If the same agency invoices a Delhi client, the invoice shows IGST 18% (₹18,000) instead — same total, different split.

Input Tax Credit (ITC) — GST Is Not a Cost for Businesses

One of the most significant features of GST is the Input Tax Credit mechanism. A GST-registered business can deduct the GST it paid on its purchases (inputs) from the GST it collects on its sales (output). Only the net difference is deposited with the government.

How ITC Works

A manufacturer buys raw materials worth ₹1,00,000 and pays GST of ₹18,000 (18%).

They sell the finished product for ₹1,50,000 and collect GST of ₹27,000 (18%).

GST payable to government = ₹27,000 − ₹18,000 = ₹9,000

The ₹18,000 paid on inputs is not a cost — it is fully recovered through ITC.

ITC is available only to registered businesses

Unregistered businesses and end consumers cannot claim ITC. For them, GST is a final cost embedded in the purchase price.

ITC cannot be claimed on blocked credits

Certain expenses — personal use, motor vehicles (with exceptions), food and beverages, club memberships — are blocked from ITC even if GST was paid.

ITC must be matched with supplier filings

ITC can only be claimed if the supplier has filed their GSTR-1 and the invoice appears in the buyer's GSTR-2B. Mismatches result in ITC denial.

GST for Consumers — What You Actually Pay

As an end consumer, you bear the full GST cost on every purchase. Unlike businesses, you cannot claim ITC. Understanding how GST is embedded in prices helps you verify bills, compare costs, and make informed purchasing decisions.

🧾

Check Your Bill

Every GST invoice must show the base price, applicable GST rate, GST amount (split into CGST + SGST or IGST), and the total. If a seller charges GST without a GSTIN on the bill, that is a red flag.

🏨

Hotels & Restaurants

Restaurant bills show 5% GST (no ITC) for most eateries. Hotels charge 12% for rooms under ₹7,500/night and 18% above. Always verify the rate matches the category.

🛍️

E-commerce Purchases

Online platforms collect GST on behalf of sellers under the TCS (Tax Collected at Source) mechanism. The GST you pay on Amazon or Flipkart is remitted by the platform, not the individual seller.

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Real Estate

Under-construction properties attract 5% GST (1% for affordable housing). Completed properties with an occupancy certificate are exempt from GST. Stamp duty and registration are separate.

GST Registration and Filing Obligations

Businesses that cross the registration threshold must register within 30 days and begin filing returns. Here is a quick overview of the key compliance requirements:

Registration Thresholds

₹40 lakh annual turnover for goods (₹20 lakh for services) in most states. ₹10 lakh in special category states (North-East, Himachal Pradesh, Uttarakhand). Certain businesses — e-commerce operators, inter-state suppliers, reverse charge recipients — must register regardless of turnover.

GSTR-1 — Outward Supplies

Filed monthly (11th of next month) or quarterly under QRMP scheme. Reports all sales invoices raised during the period. This data flows into the buyer's GSTR-2B for ITC matching.

GSTR-3B — Summary Return & Payment

Filed monthly (20th of next month) or quarterly under QRMP. Summarises output tax liability, ITC claimed, and net tax payable. Tax must be paid by the due date to avoid interest at 18% per annum.

GSTR-9 — Annual Return

Filed once a year (31 December) by regular taxpayers with turnover above ₹2 crore. Reconciles all monthly/quarterly filings for the financial year. Mandatory audit (GSTR-9C) for turnover above ₹5 crore.

Frequently Asked Questions

What taxes did GST replace in India?

GST replaced over a dozen central and state indirect taxes including Central Excise Duty, Service Tax, Central Sales Tax (CST), Value Added Tax (VAT), Entry Tax, Octroi, Entertainment Tax, and Luxury Tax. This consolidation eliminated the cascading effect of tax-on-tax that existed in the previous regime.

What is the difference between GST-exclusive and GST-inclusive pricing?

GST-exclusive pricing means the listed price does not include GST — the tax is added on top. GST-inclusive pricing means GST is already embedded in the displayed price. To extract the base price from a GST-inclusive amount, divide by (1 + GST rate/100). For example, ₹118 inclusive of 18% GST: base = 118 ÷ 1.18 = ₹100.

Who is exempt from GST registration?

Businesses below the turnover threshold (₹40 lakh for goods, ₹20 lakh for services in most states) are exempt from mandatory registration. Additionally, agriculturists supplying their own produce, individuals making only exempt supplies, and those making only non-taxable supplies are not required to register.

What is the Composition Scheme under GST?

The Composition Scheme allows small businesses with turnover up to ₹1.5 crore (₹75 lakh for services) to pay GST at a flat rate (1% for traders, 5% for restaurants, 6% for service providers) without the complexity of ITC and monthly filings. The trade-off is that they cannot charge GST on invoices or claim ITC on purchases.

Can I claim GST paid on business travel?

GST paid on air and rail tickets for business travel is eligible for ITC. However, GST on hotel accommodation is also claimable if the stay is for business purposes and the invoice is in the company's name with GSTIN. Personal travel expenses are blocked from ITC.

What happens if I file GST returns late?

Late filing attracts a late fee of ₹50 per day (₹25 CGST + ₹25 SGST) for returns with tax liability, and ₹20 per day for nil returns. Additionally, interest at 18% per annum is charged on the unpaid tax amount from the due date until the date of payment.