GST Calculator India
Calculate GST-inclusive and GST-exclusive amounts for Indian invoices, purchase checks, and supplier quotations.
No loginBrowser-side processingNo server uploads
Interactive Presets
India GST
UK/EU VAT
Global GST
Intra-State GST Breakdown (CGST & SGST 50/50 split)
Base amount
1000.00
Tax amount (18%)
180.00
Invoice Grand Total
1180.00
Business examples
- Reverse-calculate GST from a supplier invoice
- Add 18% GST to a procurement quote
- Check base value before creating an invoice
How to use it
- Use inclusive mode when the supplier gives a gross amount including GST.
- Use exclusive mode when you know the base amount and need to add GST.
- For procurement approvals, record base amount, GST amount, and gross amount separately.
FAQ
Can I calculate 18% GST?
Yes. Enter 18 in the GST rate field, or use any other rate that applies.
Is this only for invoices?
No. It is also useful for purchase approvals, quotations, landed-cost checks, and seller pricing.
Is my calculation saved?
Processing happens in your browser. FreeBizTools does not upload your files or form contents to a server in this launch version.
Use the full tool
This page is built for a specific search intent. The canonical tool stays at /tools/gst-calculator.