GST & Business

Reverse GST Calculator

Quick answer: The FinTax24 Reverse GST Calculator extracts the base price and tax amount from any GST-inclusive invoice across all five slabs (5% / 12% / 18% / 28%) for both intra-State (CGST + SGST) and inter-State (IGST) supplies. It is the standard tool for retail reconciliation, MRP back-calculation and expense-claim reclassification.

Reverse GST Calculator

Remove GST from a GST-inclusive price to find base and tax portions.

1 Enter Details

2 Results

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Click Calculate on the left to reveal the breakdown.

Disclaimer: Results are for indicative purposes only and may vary based on actual rates, rules, and policies. Please consult a FinTax24 expert for binding advice.

How to use this calculator

Follow these 4 steps for an accurate result.

  1. 1

    Enter the inclusive amount

    Type the value shown on the GST bill — typically MRP or total invoice value including tax.

  2. 2

    Choose the GST rate

    Pick 5%, 12%, 18% or 28% (or 0% for exempt categories) based on HSN/SAC classification.

  3. 3

    Pick intra vs inter-State

    Intra-State splits into CGST + SGST, inter-State uses IGST only.

  4. 4

    Read base + tax breakdown

    See base price, total tax, and CGST / SGST or IGST components instantly.

Key takeaways

  • Single-formula reverse-GST math: Inclusive × Rate / (100 + Rate) = Tax component.
  • Splits the tax into CGST + SGST (intra) or IGST (inter) based on transaction type.
  • Helps reconcile reverse-charge invoices, inter-State purchases, and TDS-claim computation.
  • Works for MRP back-calculation, expense-claim filings and composition-scheme tax adjustments.

Frequently asked questions

Quick answers to common questions about reverse gst calculator.

How do I back-calculate GST from an inclusive amount?

Tax amount = Inclusive × GST rate / (100 + GST rate). Base price = Inclusive - Tax. Example: a ₹1,180 invoice at 18% contains ₹1,000 base + ₹180 tax. Calculator handles this automatically.

Is reverse GST required for reverse-charge invoices?

Yes — for reverse-charge purchases (advocate fees, renting from unregistered landlord, GTA service, etc.), reverse-GST math determines the GST component that you must self-pay to the Government. The supplier does not collect it — you compute it on their behalf.

Does reverse GST apply on MRP-based billing?

Yes, retail customers and dealers often need to back-calculate the GST component included in MRP for GST-claim, ITC reconciliation or audit trails. Use this calculator on the printed MRP to extract the embedded tax.

What if the GST rate is 0%?

Reverse-GST on a 0% rate produces zero tax and the base price equals the invoice amount. Useful for exempted goods (fresh produce, education, healthcare) where no GST is embedded but downstream ITC-claim corrections need explicit confirmation.

How does composition scheme adjust reverse GST?

Composition taxpayers cannot claim ITC, but they often receive inclusive bills. Reverse-GST math still works — the buyer can confirm the embedded tax, but the seller (composition dealer) is exempt from collecting it. Hence the actual tax outflow may be lower for composition businesses.

Can I reverse-calculate IGST for inter-State purchase?

Yes. Choose "Inter-State" mode and the calculator shows the entire GST as IGST. For IGST adjustment against output liability, the GST portal auto-populates GSTR-2B with line-wise tax components, which the calculator numbers reconcile against.

Sources & authority: For regulations on reverse gst calculator, refer to gst.gov.in, mca.gov.in, incometax.gov.in, rbi.org.in, CBIC GST portal, CGST Act Section 9 (rate schedule), E-way Bill system.

Last reviewed by: FinTax24 Indirect Tax Desk · Reviewed on:

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