Reverse GST Calculator — Extract Base Price from MRP — FY 2026-27
Extract the base price + GST components from an inclusive amount (MRP). Useful for freelancers invoicing, businesses reconciling books, or consumers decoding receipts. Reverse formula: base = MRP / (1 + rate/100); GST = MRP − base. Our calculator supports all CBIC slabs (0/0.25/3/5/12/18/28%) and auto-splits into CGST + SGST or IGST.
Compute your numbers → GST Calculator
Use the full GST Calculator for interactive computation with your exact inputs. This page covers the specific context + rules for your query intent.
Key rules at a glance
- Extract base + tax from MRP
- All CBIC slabs supported
- Auto CGST + SGST / IGST split
- Round-trip accurate to ₹1
- Works for freelancer GST invoicing
How reverse GST works
If you see an MRP of ₹118 and you know it includes 18% GST, the base price is ₹118 ÷ 1.18 = ₹100.00, and GST is ₹18. Formula: base = inclusive / (1 + rate/100). If you know the rate AND the inclusive amount, you extract both components. This is "reverse" because normal GST adds tax to base; reverse subtracts tax from total.
When do you need reverse GST?
Three common scenarios: (1) Freelancer invoicing — client paid ₹59,000 as "inclusive of 18% GST"; you need to post ₹50,000 + ₹9,000 GST in books. (2) Retailer reconciliation — MRP printed on product includes GST; for filing GSTR-1 you need base × rate. (3) Consumer claim — B2B recipient can claim ITC on GST portion; need to know the exact GST amount from an MRP-inclusive invoice.
CGST + SGST or IGST on reverse?
Same split rules as forward GST: intra-state supply → half CGST + half SGST; inter-state → full IGST. So ₹118 MRP inclusive 18% IGST = ₹100 base + ₹18 IGST. Same amount with 18% CGST+SGST (intra-state) = ₹100 base + ₹9 CGST + ₹9 SGST. Customer pays ₹118 either way; split is administrative.
Reverse GST Calculator — FAQ
How do I reverse calculate GST from MRP?
Base price = MRP / (1 + GST rate/100). For ₹118 MRP at 18% GST: base = 118/1.18 = ₹100. GST = ₹118 − ₹100 = ₹18. Works for any rate — just substitute the slab you know.
What is the difference between forward and reverse GST?
Forward GST: you have base price, add tax to get inclusive. Reverse GST: you have inclusive amount, extract base + tax. Same formula, different direction. Both give identical results when round-tripped.
Does reverse GST apply for composition scheme?
No. Composition scheme (1-6% depending on business type) is a tax ON turnover, not collected from customer. Composition dealers cannot show GST on invoices and customers cannot claim ITC. Reverse GST only applies to regular GST regime.
Is reverse GST and RCM (Reverse Charge Mechanism) the same?
No. "Reverse GST calculator" is a math operation (extracting tax from inclusive). "Reverse Charge Mechanism" is a legal rule where the RECIPIENT pays GST instead of supplier (e.g., legal services, security agency services, unregistered supplier to registered). Don't confuse the two.
What if the MRP is exempt from GST?
Then reverse = 0. Essential items (milk, fresh vegetables, unbranded atta, sanitary pads) and some services (healthcare, education) are GST-exempt. MRP for these IS the base price — nothing to reverse-extract.
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