GST Calculator
Calculate GST instantly. Add or remove GST with all slab rates - 5%, 12%, 18%, 28%.
🧾GST Details
Price Breakdown
GST Slab Reference
How the GST Calculator Works
What Is GST and How It Replaced the Old Tax System
Goods and Services Tax (GST) is India's unified indirect tax, introduced on 1 July 2017. It replaced a fragmented system of taxes — VAT, service tax, excise duty, octroi, entertainment tax, and others — with a single tax on the supply of goods and services. The stated goal: one nation, one tax, one market.
GST is a destination-based tax — it accrues to the state where goods or services are consumed, not where they're produced. This eliminates the cascading effect of taxes on taxes (the old system charged tax on tax at every stage). The net effect: lower prices for most goods and simplified compliance for businesses.
There are four primary GST slabs in India: 5%, 12%, 18%, and 28%. Essential items (fresh vegetables, milk, grains, healthcare, education) attract 0% GST. Luxury and 'sin' goods (tobacco, aerated drinks, high-end cars) attract 28% plus additional cess that can push the effective rate above 40%.
CGST vs SGST vs IGST — What's the Difference?
For intra-state transactions (buyer and seller in the same state), GST is split into two equal halves: CGST (Central GST) goes to the central government, and SGST (State GST) goes to the state government. So an 18% GST becomes 9% CGST + 9% SGST.
For inter-state transactions (buyer and seller in different states), a single IGST (Integrated GST) is charged instead. The IGST is collected by the central government, which then distributes the state's share to the destination state. From the consumer's perspective, the total tax rate is the same — only the collection mechanism differs.
The split matters for businesses filing GST returns (they need to track CGST, SGST, and IGST separately) but not for consumers calculating their payable amount. Our calculator shows the CGST/SGST split for reference, matching the standard breakdown on GST invoices.
GST Inclusive vs Exclusive — The Critical Distinction
GST-exclusive price is the base price before tax is added. If a service provider quotes ₹10,000 plus 18% GST, the total is ₹11,800. This is common for B2B transactions where the buyer wants to see the base cost clearly.
GST-inclusive price is the final price already including tax. Most retail MRPs are GST-inclusive — when you buy a ₹1,180 electronic accessory, the MRP includes the base price of ₹1,000 plus ₹180 GST. This makes it easier for consumers to see what they'll actually pay, but harder to reverse-engineer the base price.
To find the base price from a GST-inclusive amount, the formula is: Base = Total × 100 / (100 + GST Rate). For ₹1,180 at 18% GST: Base = 1,180 × 100 / 118 = ₹1,000. Our calculator handles both directions — 'Add GST' for exclusive-to-inclusive, 'Remove GST' for inclusive-to-exclusive.
Step-by-Step Worked Example
You run a small business and invoice a client ₹10,000 for services. The applicable GST rate is 18%. Let's calculate the total amount and the CGST/SGST split.
- 1Base price (GST exclusive): ₹10,000.
- 2GST amount = ₹10,000 × 18 ÷ 100 = ₹1,800.
- 3CGST (Central GST, 9%) = ₹1,800 ÷ 2 = ₹900.
- 4SGST (State GST, 9%) = ₹1,800 ÷ 2 = ₹900.
- 5Total invoice value = ₹10,000 + ₹1,800 = ₹11,800.
Result
Base price: ₹10,000
CGST (9%): ₹900
SGST (9%): ₹900
Total GST: ₹1,800
Invoice total: ₹11,800
Reverse case: If a customer's invoice total is ₹11,800 with 18% GST inclusive, the base price is ₹11,800 × 100 ÷ 118 = ₹10,000, and GST is ₹1,800.
Key Benefits & Use Cases
When to Use This Tool
- ✓Businesses calculating GST to add to invoices for services or goods.
- ✓Consumers verifying whether an MRP includes GST or not.
- ✓Freelancers and consultants who need to quote GST-inclusive and GST-exclusive prices.
- ✓E-commerce sellers listing products with correct GST calculations.
- ✓Anyone doing GST reconciliation for tax filing or audit purposes.
Why It Matters
- →Instant calculation — no manual math errors.
- →Supports all GST slabs (0%, 3%, 5%, 12%, 18%, 28%) plus custom rates.
- →Shows the CGST/SGST split, matching standard GST invoice format.
- →Works both ways — add GST to base price, or remove GST from inclusive price.
- →Free, no signup, works on any device.
Who Should Use This Calculator
- ★Small business owners and freelancers who need to compute GST on the fly.
- ★Consumers checking if a listed price is GST-inclusive or exclusive.
- ★Accountants preparing GST reconciliation or client invoices.
- ★E-commerce sellers setting prices for their products.
Add GST
Calculate total price after adding GST to base amount.
Remove GST
Find base price by removing GST from inclusive amount.
CGST + SGST Split
See detailed split of CGST and SGST components.
How to Use
Choose Type
Select Add GST or Remove GST based on your need.
Enter Amount
Enter the base price or GST-inclusive price.
Select GST Rate
Choose from standard rates or set a custom rate.
View Breakdown
See CGST, SGST split and total amount instantly.
The Formula
GST = (Price × GST Rate) / 100Frequently Asked Questions
What is GST?
GST (Goods and Services Tax) is an indirect tax levied on the supply of goods and services in India. It replaced multiple taxes like VAT, service tax, and excise duty on 1 July 2017, creating a unified national market with a single tax structure.
What are the GST slab rates?
There are four primary GST slabs: 5%, 12%, 18%, and 28%. Essential items (fresh produce, healthcare, education) have 0% GST. Luxury and sin goods (tobacco, luxury cars) attract 28% plus cess that can push the effective rate above 40%.
What is CGST and SGST?
CGST (Central GST) goes to the central government and SGST (State GST) goes to the state government. For intra-state transactions, both are charged equally — 18% GST becomes 9% CGST + 9% SGST. For inter-state transactions, IGST is charged instead.
How to calculate GST from MRP?
If MRP includes GST, use the Remove GST option. Base Price = MRP × 100 / (100 + GST Rate). For example, if MRP is ₹1,180 with 18% GST, base price is ₹1,000 and GST amount is ₹180.
What is the difference between GST exclusive and inclusive?
GST exclusive means GST is added on top of the base price (e.g., ₹1,000 + 18% GST = ₹1,180). GST inclusive means the price already includes GST (e.g., MRP of ₹1,180 includes ₹180 GST and ₹1,000 base price). Most retail MRPs are GST inclusive.
What is IGST?
IGST (Integrated GST) is charged on inter-state transactions — when goods or services are supplied across state borders. It's collected by the central government, which distributes the state's share to the destination state. The rate is the same as the equivalent CGST+SGST combined.
What is the 5% GST rate applicable to?
The 5% slab covers items like packaged food, economy class air travel, small restaurants, and certain mass-consumption goods. It's one of the lowest non-zero rates, applied to items that need moderate taxation without burdening consumers heavily.
Can I use this calculator for GST filing?
This calculator is for estimation and verification. For GST filing, use the official GST portal or your accounting software (Tally, Zoho Books, ClearTax). The calculations here match standard GST rules and can be used to cross-check invoices.
Reviewed by AutoWealthLab Editorial Team
This calculator and its accompanying guide are maintained by the AutoWealthLab editorial team. Every formula is verified against standard financial references, and results are cross-checked with independent calculators before publishing. Our tools are updated whenever tax rules, interest rate benchmarks, or regulatory formulas change.
Last reviewed: October 2026 · Methodology: Standard amortization and compound interest models · Learn more about our testing process