Given a GST-inclusive total, extract the base amount and GST component with CGST/SGST/IGST split.
The Reverse GST calculator extracts the base value and tax component from a GST-inclusive amount — essential for MRP-based purchases, restaurant bills, and B2C invoices where the tax is embedded. Formula: Base = Inclusive / (1 + rate/100); GST = Inclusive − Base.
This matters for accurate bookkeeping (base goes to P&L / inventory; GST goes to ITC ledger) and for margin analysis when suppliers quote inclusive prices. Combine with our HSN/SAC Finder to confirm the correct rate before reverse-calculating.
Business meal at a non-AC restaurant, need to book expense + ineligible ITC separately.
Claiming ITC on blocked items (food/beverage, motor vehicles <13 seats, personal use) — Section 17(5).
Applying wrong rate — verify HSN/SAC first.
Need a CA to review your numbers? Book a free consult — we'll double-check within 24 hours.
Segregate blocked-ITC expenses in a separate ledger for annual GSTR-9 reconciliation.
When a supplier gives you a GST-inclusive price and you need to break it into base + GST for invoicing or ITC reconciliation.
Yes. You must know the applicable rate to correctly extract the GST component.
When a supplier gives you a GST-inclusive price and you need to break it into base + GST for invoicing or ITC reconciliation.
via Reverse GST CalculatorYes. You must know the applicable rate to correctly extract the GST component.
via Reverse GST CalculatorGST is mandatory only if your turnover exceeds the GST threshold. Otherwise PAN is enough.
via MSME / Udyam RegistrationNo. Processing fees, insurance, GST on fees and stamp duty are excluded and vary per lender. Add them separately to arrive at the true cost of the loan.
via EMI CalculatorNo. Processing fees, insurance, GST on fees and stamp duty are excluded and vary per lender. Add them separately to arrive at the true cost of the loan.
via Personal Loan CalculatorThis dataset is free to reference in articles, research and reports. Attribution to Taxpex Consultancy is all we ask. Data last verified 31 July 2026.
Taxpex Consultancy. (2026). Reverse GST Calculator — Taxpex. Retrieved from https://taxpex.com/tools/gst/reverse-gst-calculator<a href="https://taxpex.com/tools/gst/reverse-gst-calculator">Reverse GST Calculator — Taxpex</a> — Taxpex Consultancy