Business Tool

GST Calculator – Add or Remove GST

Calculate CGST, SGST, IGST and totals for all GST rates including 5%, 18% and 40%. Perfectly formatted for Indian business standards.

Base Amount (₹) *

₹

Calculation Type

GST Tax Slab

Calculating...

Calculation Summary

Net / Base Price:

CGST ():

SGST ():

Total Tax Amount (IGST):

Final Inclusive Amount

How to Use the GST Calculator

Enter Amount

Provide your bill amount. It can be just the base price of your commodity, or the total inclusive amount you received.

Select Slab & Type

Choose "+ Add GST" to apply tax on top of your amount. Choose "- Remove GST" to reverse-calculate the hidden tax inside the total.

Copy Result

The correct CGST, SGST and IGST breakdowns calculate automatically. Copy them straight into your accounting books.

GST in India - What Every Business Owner Must Know

GST simplified indirect taxation by merging multiple central and state taxes into a unified framework. Correct GST calculations are essential for compliant invoicing and accurate pricing.

Whether you are adding GST to base prices or reverse-calculating tax from inclusive totals, fast and error-free computation saves time and reduces filing issues.

This calculator helps businesses, freelancers, and accountants quickly compute total GST, taxable value, and tax split components.

💼 GST Compliance and Tax Planning Tips

Track Thresholds

Monitor turnover and interstate supply criteria to determine timely registration obligations.

File on Time

Maintain return calendars to avoid late fees, interest, and input credit disruptions.

Use Correct HSN/SAC

Accurate classification reduces mismatch notices and improves return consistency.

Reconcile Regularly

Match invoices, ledgers, and portal data monthly to catch tax differences early.

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About the GST Calculator

The GST Calculator adds or removes GST on any amount at the current rates of 0%, 3%, 5%, 18% and 40% (in force since 22 September 2025) and splits the tax into CGST and SGST. Enter the amount, choose the rate and whether GST is included, and read the totals instantly. It runs in your browser and nothing is stored.

GST Calculator quick facts

Rates:

0%, 3%, 5%, 18% and 40%, in force since 22 September 2025

Add GST:

Price × rate, then add it to the price

Remove GST:

Divide the total by 1 plus the rate. ₹11,800 at 18% gives ₹10,000 and ₹1,800 GST

Split:

CGST and SGST each take half of the rate within a state

How to use the GST Calculator

Enter the base or GST-inclusive amount in rupees.
Pick the GST slab and choose Add GST or Remove GST.
Read the net price, CGST, SGST and total, then copy or download the result.

How GST is calculated

GST is a percentage of the price before tax. To add GST, multiply the base price by the rate and add the result: total = base × (1 + rate ÷ 100).

To remove GST from a price that already includes it, divide by 1 plus the rate: base = total × 100 ÷ (100 + rate). The GST is the total minus the base.

Current GST rates in India

On 3 September 2025 the GST Council approved a simpler structure, in force from 22 September 2025: a standard rate of 18%, a lower rate of 5% for essentials, and a special 40% rate for a few luxury and sin goods. The 12% and 28% slabs were removed. Some items keep special rates, for example 3% for gold, and many supplies remain exempt.

Which rate applies depends on the HSN or SAC code of what you sell, so always confirm it in the official rate schedule.

CGST, SGST and IGST

When you sell within one state, the GST is split equally between the Centre (CGST) and the state (SGST). At 18% that is 9% CGST and 9% SGST. When you sell to another state, the whole amount is charged as IGST.

Worked example

A service priced at ₹25,000 before tax, sold within the same state at 18%: GST is ₹4,500 (CGST ₹2,250 plus SGST ₹2,250), so the invoice total is ₹29,500.

Going the other way, a ₹29,500 price that includes 18% GST works out to ₹29,500 × 100 ÷ 118 = ₹25,000 before tax.

Common mistakes

Adding GST to a price that already includes it, using a retired 12% or 28% rate on a new invoice, applying the wrong HSN code, and mixing CGST/SGST with IGST on the same invoice.

Frequently asked questions about the GST Calculator

How do I calculate GST on a price?

Multiply the base price by the GST rate and add it. For example, ₹10,000 at 18% GST is ₹1,800 of tax, so the total is ₹11,800.

How do I remove GST from a GST-inclusive price?

To remove GST from a price that already includes it, divide the total by 1 plus the GST rate as a decimal. For example, a total of ₹11,800 at 18% GST gives a base price of ₹10,000 and ₹1,800 of GST. Use the Remove GST option for this.

What is the difference between CGST, SGST and IGST?

For sales within a state the GST is split equally into CGST (central) and SGST (state). For sales between states the full amount is charged as IGST.

What are the GST rates in India now?

Since 22 September 2025 the main rates are 5% and 18%, with 40% for a few luxury and sin goods, 3% for items such as gold, and 0% for exempt supplies. The earlier 12% and 28% slabs were removed. Check the CBIC rate notification for the exact rate of your product or service.

Which GST rate applies to my product?

It depends on the HSN code (goods) or SAC code (services). Look up the code in the official GST rate schedule; this calculator does not decide the rate for you.

What if my invoice is dated before 22 September 2025?

Supplies made before that date were charged at the old slabs, including 12% and 28%. This calculator now offers only the current rates, so work out older invoices by hand using the formulas above.

How do I calculate GST on an MRP?

The MRP already includes GST, so choose Remove GST rather than Add GST. Divide the MRP by 1 plus the rate to get the price before tax, then subtract that from the MRP to see how much of it is GST.

Does GST apply to every business?

Businesses below the registration threshold, and composition-scheme dealers, do not collect GST in the usual way. Ask your accountant which applies to you.

How should GST be rounded on an invoice?

Round the tax amount to the nearest rupee or paise as your accounting software does, and keep one method for the whole invoice so totals match.

Free, no sign-up. Reviewed 15 October 2026 by the Gopafy team. See all free tools.