Free Online GST Calculator

Add or remove Goods and Services Tax (GST) percentages from product prices instantly.

Understanding Goods and Services Tax (GST)

The Goods and Services Tax (GST) is an indirect tax levied on the supply of goods and services. It has consolidated numerous historical indirect taxes (such as VAT, service tax, excise duty, and luxury tax) into a single, unified taxation system. Businesses must accurately compute GST to maintain compliance with government regulations, draft error-free invoices, and set accurate consumer pricing.

Key Benefits & Features

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Accurate IGST, CGST & SGST Splits

Calculates central, state, and integrated tax components in real-time.

✓

Reverse GST Calculation

Easily subtract GST from gross invoice totals to determine net cost.

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100% Free & Unlimited

Perform instant tax calculations for invoices and quotes with zero signups.

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Business Invoice Ready

Ideal for freelancers, small business owners, accountants, and e-commerce sellers.

How to Use the GST Calculator Step-by-Step

This utility runs entirely inside your browser using client-side JavaScript. We prioritize your security: none of your inputted text is logged or stored.

1
Enter Net/Gross Amount: Input your starting transaction amount.
2
Select GST Rate: Choose standard tax rates (5%, 12%, 18%, 28%) or enter a custom rate.
3
Calculate Tax: Toggle between "Add GST" or "Remove GST" to view CGST, SGST, IGST, and final totals.

Practical Examples

Input Example

Net: $1200, Rate: 18%, Mode: Add GST

Expected Output

Gross Total: $1416, Total GST: $216 (CGST: $108, SGST: $108)

Input Example

Amount: $590, GST: 18%, Action: Remove GST

Expected Output

Base Price: $500.00, GST Amount: $90.00 (CGST: $45.00, SGST: $45.00), Gross Price: $590.00

Input Example

Amount: $10,000, GST: 28%, Action: Add GST

Expected Output

Base Price: $10,000.00, GST Amount: $2,800.00, Gross Price: $12,800.00

Frequently Asked Questions (FAQ)

What is the difference between CGST, SGST, and IGST?▼

CGST (Central GST) and SGST (State GST) are levied on transactions within a single state and are split equally. IGST (Integrated GST) is levied on transactions between different states and goes directly to the Central government, which shares it with the destination state.

How do you calculate the price excluding GST?▼

To exclude GST from a total price, divide the total price by (1 + GST rate / 100). The result is the base price. Subtracting the base price from the total price gives the tax amount.

Can this calculator be used for international taxes like VAT?▼

Yes, VAT and GST use the same mathematical percentage formulas. If you want to compute VAT, simply enter the VAT rate in the tax percentage field and use the add/remove options.

Is tax split always 50/50 between state and federal?▼

For intrastate sales under GST, the tax is always split equally between CGST and SGST. For interstate sales, the entire rate is applied as IGST, which does not require an inline split.

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