GST Calculator

The amount

Amount before GST

GST rate (%)

Slabs checked on 3 October 2026. Confirm the rate for your item.

Quick rates

Base amount: 10,000.00
GST: 1,800.00
CGST (half): 900.00
SGST (half): 900.00
Total: 11,800.00

Quick facts

Price: Free
Sign-up: Not required
Where it runs: On your device
Files uploaded: No
Limits: No fixed limit
Updated: October 3, 2026

GST Calculator adds Goods and Services Tax to a price, or takes it out of a price that already includes it, and splits the tax into CGST and SGST. It is meant for shop owners, freelancers and buyers in India who need to check an invoice or quote a price quickly. You can type any rate, or pick one of the current slabs with a single tap.

How to use

Choose Add GST when your amount is before tax, or Remove GST when it already includes tax.
Type the amount, in rupees or any other unit; only arithmetic is done.
Type the GST rate, or tap a quick rate button: 5%, 18% or 40%.
Read the Base amount, the GST, its two halves CGST and SGST, and the Total.

The quick rates are the slabs we found in force when we checked the official GST Council and Government of India announcements on 3 October 2026: 5%, 18% and a special 40% rate, effective from 22 September 2025, alongside nil rated items. Rates for a particular item can differ and can change, so you must confirm the rate for your item yourself.

Examples

Adding 18% GST to 10,000 gives GST of 1,800.00, split into CGST 900.00 and SGST 900.00, and a total of 11,800.00.

Removing 18% GST from 11,800 works backwards: the base is 11,800 × 100 ÷ 118, which is 10,000.00, and the GST inside it is 1,800.00. Notice that removing 18% is not the same as taking 18% off the total, which would give 9,676.00.

Limits

The CGST and SGST split applies to a sale within one state; a sale between states carries IGST at the full rate instead, which is the GST figure shown. The tool does not know the rate of any item, does not include compensation cess, and does not file returns. Amounts up to 1,000,000,000,000 and rates from 0 to 100% are accepted; those limits are our own choice. Results are rounded to two decimals for display only.

FAQ

Which GST rate should I use for my product?

Look up the HSN or SAC code of your item in the official rate notifications, or ask your tax adviser. This page only does the arithmetic for the rate you choose.

Why are CGST and SGST each half of the GST?

For a supply within a state, the tax is shared equally between the central government and the state, so each half is printed on the invoice separately.

How do I find the GST inside a price that already includes it?

Choose Remove GST. The tool divides the inclusive price by one plus the rate, and the difference is the tax.