What is a GST calculator?

A GST calculator is a tool that helps you work out how much Goods and Services Tax applies to an amount, and what the final price looks like once that tax is added or removed.

How is GST calculated?

To add GST, multiply the base amount by the GST rate and divide by 100, then add that to the base amount. To remove GST from an inclusive amount, divide the inclusive amount by (1 + rate/100) to get the base amount.

How do I calculate 18% GST?

Multiply the amount by 18 and divide by 100 to get the GST amount, then add it to the original amount for the total. For ₹10,000, that's ₹1,800 GST and a total of ₹11,800.

CGST stands for Central Goods and Services Tax. It is the share of GST collected by the Central Government on transactions within the same state.

SGST stands for State Goods and Services Tax. It is the share of GST collected by the State Government on transactions within the same state, and is usually equal to CGST.

IGST stands for Integrated Goods and Services Tax. It applies to transactions between two different states or a state and a union territory, instead of splitting the tax into CGST and SGST.

What is GST-inclusive pricing?

GST-inclusive pricing means the quoted amount already contains GST, so the taxable value and tax portion need to be separated out from that total.

What is GST-exclusive pricing?

GST-exclusive pricing means the quoted amount does not yet include GST, so GST is calculated and added on top to arrive at the final payable amount.

How do I remove GST from an amount?

Switch the calculator to Remove GST mode, enter the GST-inclusive amount, and it will divide that figure by (1 + rate/100) to show the original taxable value and the GST portion.

Can I calculate GST after discount?

Yes. Turn on the discount toggle, enter a percentage or fixed discount, and GST will be calculated on the taxable amount that remains after the discount is applied.

Can I use this GST calculator for invoices?

You can use the invoice-style summary to see a clear breakdown of taxable value, CGST, SGST or IGST, and the grand total, and copy, print or share it as a reference.

Are GST calculator results legally binding?

No. Results are estimates for general informational purposes only and are not a substitute for official filings or advice from a qualified tax professional.

How accurate is this GST calculator?

The arithmetic follows standard GST formulas and is accurate for the numbers you enter, but actual applicable rates and treatment depend on the specific goods, services and rules that apply to your transaction.

Oracle GST – GST Calculator India: CGST, SGST & IGST Online

GST CALCULATOR

Calculate your GST in seconds

Enter an amount, pick a GST rate and choose how tax should apply. Every figure below updates instantly as you type.

Calculation mode

Enter Amount iThe base taxable amount before GST is added.

Please enter a valid amount of ₹0 or more.

GST rate iThe percentage of tax applicable on this transaction.

Custom rate %

Supply type

Apply discount

Discount cannot exceed the taxable amount.

Grand Total

₹11,800

Base Amount₹10,000

Taxable Amount₹10,000

GST Rate18%

CGST₹900

SGST₹900

Total GST₹1,800

Taxable Amount — ₹10,000

GST Amount — ₹1,800

Taxable Amount₹10,000

GST Amount₹1,800

Total Amount₹11,800

GST Calculation Summary

GST FEATURES

Everything you need for GST calculations

One calculator, every common GST scenario. Tap a card to jump straight into that mode.

GST

GST Calculator

Add GST to any base amount at a chosen rate.

C

CGST Calculator

See the Central GST portion on intra-state supplies.

S

SGST Calculator

See the State GST portion alongside CGST.

I

IGST Calculator

Calculate integrated GST for inter-state supplies.

₹

GST Inclusive Calculator

Work backward from a tax-inclusive price.

%

GST Exclusive Calculator

Add GST on top of a tax-exclusive price.

⟲

Reverse GST Calculator

Extract the taxable value from a final amount.

▤

GST Invoice Calculator

Get an invoice-ready breakdown you can copy or print.

−

GST Discount Calculator

Apply a discount before GST is calculated.

⇄

GST Rate Comparison

Compare totals across every GST slab at once.

τ

Taxable Value Calculator

Isolate the taxable value from a gross figure.

Σ

Invoice Total Calculator

Get the final payable amount after tax and discount.

HOW IT WORKS

How GST calculation works

Four straightforward steps take you from a raw amount to a complete GST breakdown.

01

Enter amount

Type in the base or inclusive amount you want to calculate GST on.

02

Select GST rate

Choose a standard slab or enter a custom rate for your transaction.

03

Choose tax type

Pick CGST + SGST for intra-state supply, or IGST for inter-state supply.

04

Get final amount

Read off the taxable value, GST split and grand total instantly.

INCLUSIVE VS EXCLUSIVE

GST-inclusive vs GST-exclusive pricing

The direction of the calculation depends on whether your starting amount already includes tax.

GST EXCLUSIVE

Tax added on top

The quoted price does not yet include GST — it's added afterward to reach the final amount.

₹10,000 + 18% GST = ₹11,800

GST INCLUSIVE

Tax already included

The quoted price already contains GST — the calculator separates it back into base and tax.

₹11,800 incl. 18% GST
= ₹10,000 taxable + ₹1,800 GST

GST BASICS

What is GST?

GST, or Goods and Services Tax, is an indirect tax applied to the supply of most goods and services in India. It replaced several earlier indirect taxes with a single tax structure that is collected at each stage of the supply chain and ultimately borne by the end consumer. This calculator is an estimation tool for that structure — it does not offer tax or legal advice.

CGST

Central Goods and Services Tax — the share of GST collected by the Central Government on transactions within the same state.

SGST

State Goods and Services Tax — the share collected by the State Government, charged alongside CGST within the same state.

IGST

Integrated Goods and Services Tax — charged instead of CGST/SGST when goods or services move between two different states.

GST RATES

Compare GST rates

Enter an amount to see how each GST slab changes the tax and final total.

Base amount for comparison

GST Rate	GST Amount	CGST	SGST	Final Amount

Common GST rate slabs

GST Rate	Common Use Example
0%	Essential unbranded food staples and specific exempt goods/services
5%	Select household essentials and everyday food items
12%	Certain processed foods and standard goods categories
18%	Most standard goods and services, including many professional services
28%	Select luxury and sin-category goods

Note: GST rates can depend on the specific goods/services and applicable rules. Verify the applicable rate for your transaction with an official source or professional before relying on it.

PRICE BREAKDOWN

From price to final invoice

Here's how a product or service price moves through discount and tax to become the final invoice amount, using your current calculator inputs.

WHO IT'S FOR

Built for how Indian businesses actually invoice

A GST calculator can help estimate invoice totals quickly — it's not a replacement for professional tax or accounting advice.

Retail

Quote GST-inclusive shelf prices to customers in seconds.

E-commerce

Check GST on listed prices across different product categories.

Freelancers

Add GST correctly to service invoices before sending them out.

Consultants

Break down CGST/SGST or IGST depending on the client's state.

Agencies

Estimate totals on retainer or project-based invoices.

Service businesses

Apply discounts and GST together for accurate quotes.

Manufacturers

Compare how different GST slabs affect landed cost.

Small businesses

Get quick, clear GST figures without spreadsheets.

SAVED LOCALLY

Recent calculations

Your last five calculations are stored only in this browser's local storage. Nothing is ever sent to a server.

This GST calculator is provided for general informational and estimation purposes only. GST rates, applicability, exemptions, classifications and tax rules may change and can depend on the specific goods or services and transaction circumstances. This tool does not constitute tax, legal or accounting advice. Verify the applicable GST treatment with official government sources or a qualified professional before filing or making tax decisions.

FAQ

Frequently asked questions

Common questions about how GST calculation works and how to use this tool.