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GST Calculator Online Free – Add or Remove GST
Enter an amount and a tax rate to add GST (or any VAT / sales tax) to a price, or remove it from an inclusive price, with the CGST/SGST split. Everything is calculated in your browser – nothing is uploaded or saved.
Quick answer
Quick answer: To add GST, multiply the price by (1 + rate/100) – ₹1,000 at 18% becomes ₹1,180. To remove GST from an inclusive price, divide by (1 + rate/100) – ₹1,180 ÷ 1.18 = ₹1,000. Since 22 September 2025 the main GST slabs are 5%, 18% and 40% (plus nil-rated goods).
How to use
Formula / how it works
Exclusive: GST = amount × rate/100. Inclusive: base = amount ÷ (1 + rate/100). Within a state, GST is split equally into CGST and SGST; between states the full amount is IGST.
Results are estimates for guidance. Your bank, employer or official documents are always final.
🔒 Privacy: this tool runs entirely in your browser. Nothing you type is saved, uploaded or sent anywhere – close the tab and it is gone.
More details
GST on ₹1,000 – worked examples
| GST rate | CGST + SGST (intra-state) | GST added to ₹1,000 | Total (inclusive) | Base inside ₹1,000 inclusive |
|---|---|---|---|---|
| 5% | 2.5% + 2.5% | ₹50 | ₹1,050 | ₹952.38 |
| 18% | 9% + 9% | ₹180 | ₹1,180 | ₹847.46 |
| 40% | 20% + 20% | ₹400 | ₹1,400 | ₹714.29 |
For an inter-state sale the whole amount is charged as IGST at the same total rate (for example 18% IGST instead of 9% CGST + 9% SGST). A few special rates also exist, such as 3% on gold and 0.25% on rough diamonds, and some tobacco products continue on older rates for now – enter any rate in the GST % box.
Source: PIB note on the GST rate changes from 22 September 2025 and CBIC Notification No. 9/2025-Central Tax (Rate). Check the rate for your HSN/SAC code before you invoice.
Related: percentage calculator, discount calculator and purchase order generator.
FAQ
Frequently asked questions
Is the result exact?
The formula is standard, but banks and employers may round differently or add charges, so small differences are possible.
Is my data saved?
No. Everything is calculated in your browser and nothing is sent anywhere.
Does it work on mobile?
Yes, in any modern browser on Android, iPhone, tablet or computer.
Do I need an internet connection?
Only to open the page. After it loads, the calculator also works offline.
What are the GST rates in India now?
From 22 September 2025 most goods and services fall in two slabs, 5% and 18%, with 40% for luxury and sin goods. Some items are nil-rated, and a few special rates such as 3% for gold remain.
How do I remove 18% GST from a price?
Divide the inclusive price by 1.18. For ₹1,180 that gives a base of ₹1,000, and the GST is ₹180 (₹90 CGST + ₹90 SGST within a state).
When is IGST charged instead of CGST and SGST?
IGST applies to inter-state supplies and imports. For a sale within one state, the same total rate is split equally into CGST and SGST.