What is the exact formula to remove GST from a GST-inclusive price?

To remove GST from an inclusive price, divide the inclusive price by (1 + GST Rate / 100). For example, for ₹1,180 inclusive of 18% GST: Taxable Value = 1180 ÷ 1.18 = ₹1,000, and GST Amount = ₹1,180 − ₹1,000 = ₹180.

Why is subtracting 18% directly from an inclusive price wrong?

Because the 18% tax was originally added on top of the 100% base price (making the total 118% of the base). If you subtract 18% of ₹1,180, you get ₹212.40 instead of the true ₹180 tax, understating your taxable revenue and overstating tax.

When should I use GST-inclusive vs GST-exclusive pricing?

In India, consumer retail prices (MRPs) in stores and B2C e-commerce must legally be GST-inclusive. B2B wholesale trade, corporate contracts, and service quotations typically quote GST-exclusive base prices plus applicable GST.

Can I use this for 18% professional or software services?

Yes. If you agree to a fixed fee of ₹25,000 inclusive of 18% GST, select 'GST Inclusive' and 18% to see that your invoice should list ₹21,186.44 as the service fee and ₹3,813.56 as GST.

How are odd paisa decimals handled on GST invoices?

Line-item taxable values and CGST/SGST amounts are recorded to 2 decimal places (paisa), while the final invoice payable amount can be rounded to the nearest whole rupee under Section 170 of the CGST Act.

GST Inclusive / Exclusive Calculator — Reverse & Forward GST

Calculation Direction

GST Inclusive Total (MRP / Bill Amount)

₹

GST Rate

Custom percentage:

GST Removed (Reverse)18% Rate

Original (Pre-tax Base):₹10,000.00

Total GST Amount (18%):₹1,800.00

CGST (9%):₹900.00

SGST (9%):₹900.00

or IGST (18%):₹1,800.00

Pre-Tax Base Amount₹10,000.00You save ₹1800.00 in input tax credit

Formulas Used

GST Inclusive Formula (Reverse)

Base Price = Inclusive Amount / (1 + (Rate / 100))

GST Amount = Inclusive Amount - Base Price

Use when the price already includes taxes (such as retail MRP or restaurant bills).

GST Exclusive Formula (Forward)

GST Amount = (Base Price × Rate) / 100

Total Amount = Base Price + GST Amount

Use when quoting B2B rates or freelancing contracts before adding statutory GST.

How to Use the GST Inclusive / Exclusive Price Calculator

1
Select your calculation direction: GST Inclusive (remove tax from total) or GST Exclusive (add tax to base).
2
Enter the rupee amount (₹) from your receipt, MRP sticker, or wholesale quote.
3
Choose the applicable GST slab (3%, 5%, 12%, 18%, 28%, or custom rate).
4
Inspect the pre-tax taxable value, exact GST component (CGST + SGST or IGST), and final payable total.

Practical Use Cases

Retail Shopkeepers & E-Commerce Sellers

Extracting Taxable Value from MRP Sales

When selling a product at ₹999 MRP (inclusive of 18% GST), reverse-calculate the exact ₹846.61 taxable value and ₹152.39 GST required for your GSTR-1 invoice.

Accountants & Bookkeepers

claiming Input Tax Credit (ITC) from Receipts

Verify whether a vendor's tax-inclusive bill has separated the base cost and GST accurately before booking Input Tax Credit in Tally or Zoho Books.

Freelancers & Service Providers

Handling 'All-Inclusive' Client Budgets

When a client insists on a flat ₹50,000 budget inclusive of GST, quickly find your net ₹42,372.88 service fee and ₹7,627.12 GST liability.

GST Inclusive / Exclusive Price Calculator Features

Two-Way Reverse & Forward Math

Quickly strip out GST to find the pre-tax base cost or add GST on top of net quotations.

Accurate Decimal Rounding

Matches standard Indian accounting and GST portal rounding rules to the nearest paisa.

Complete Tax Breakdown

Shows both combined GST and component-wise CGST, SGST and IGST values.

100% Private & In-Browser

Calculations and document previews run entirely in your web browser. No financial data is ever stored on our servers.

Free for Indian Businesses

Created specifically for freelancers, consultants, shop owners, traders and MSMEs across India with zero subscription costs.

Mobile & Print Ready

Optimized for one-hand mobile input, instant copy actions, and clean A4 printable layouts.

Technical Specifications & Best Practices

✓Reverse GST uses the statutory formula `Taxable Value = Inclusive Amount ÷ (1 + Rate/100)`—never simply subtract 18% directly from the gross total.
✓Displays both combined GST and split CGST (half) + SGST (half) figures for immediate entry into accounting software.
✓All values are rounded to 2 decimal places (nearest paisa) to prevent rounding discrepancies between base + tax and total.
✓100% browser-based execution with zero server logging.

GST Inclusive / Exclusive Price Calculator