RSRobince Studio

GST Calculator

Calculate GST in seconds. Add tax to a net price or extract the tax from a total, with the CGST and SGST split shown automatically.

Runs in your browser. Your files are never uploaded.

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How to use GST Calculator

  1. Choose Add GST or Remove GST.
  2. Enter the amount and pick the GST rate.
  3. Read the net amount, GST, CGST/SGST and total.

How GST is calculated

Goods and Services Tax is a percentage added to the value of goods or services. If the price is quoted without tax, GST = price × rate ÷ 100 and the total is price + GST. If the quoted price already includes tax, the net price is total ÷ (1 + rate ÷ 100) and the GST is the difference.

Intra-state vs inter-state

  • Same state: GST splits into CGST and SGST, each half of the rate (9% + 9% for an 18% slab).
  • Different states: the full rate is charged as IGST.
  • Union territories without a legislature use UTGST in place of SGST.

Check current rates

GST rates and slabs are set by the GST Council and change from time to time, and different goods fall into different slabs. This calculator does the arithmetic for whichever rate you enter, but always confirm the rate for your product with the official GST rate schedule or your accountant. The tool is for estimates, not tax advice.

Why use this gst calculator tool

  • Add or remove GST. Works for exclusive and inclusive prices.
  • CGST / SGST / IGST. Intra-state and inter-state split shown.
  • Common slabs. Quick pick for 0, 3, 5, 12, 18 and 28%.

Frequently asked questions

How do I add 18% GST?

Multiply the net price by 1.18. For 1,000 the GST is 180 and the total is 1,180.

How do I remove GST from a total?

Divide the GST-inclusive price by 1 + rate. At 18%, divide by 1.18. 1,180 ÷ 1.18 = 1,000, so the GST is 180.

What is the difference between CGST, SGST and IGST?

For sales within one state, GST is split equally into Central GST and State GST. For sales between states, the whole amount is charged as Integrated GST (IGST).

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