GST Calculator

FREEFinance & Business

TOOLGST Calculator

Amount (Rs)

₹10,000.00

Mode

Transaction Type

Quick:

Add GST: Enter the base/exclusive price. GST is calculated on top of this amount.

Results — All GST Slabs

GST Rate	Base Amount	CGST	SGST	Total (GST incl.)
0%	₹10,000.00	—	—	₹10,000.00
5%	₹10,000.00	₹250.00	₹250.00	₹10,500.00
12%legacy · pre-Sept 2025	₹10,000.00	₹600.00	₹600.00	₹11,200.00
18%standard	₹10,000.00	₹900.00	₹900.00	₹11,800.00
28%legacy · pre-Sept 2025	₹10,000.00	₹1,400.00	₹1,400.00	₹12,800.00
40%de-merit	₹10,000.00	₹2,000.00	₹2,000.00	₹14,000.00

Your Amount (Base)

₹10,000.00

GST @ 18% (CGST + SGST)

₹1,800.00

Total Payable

₹11,800.00

How This Compares to Other Free GST Tools

Feature	Typical bank/GST portal calculators	Typical online GST calculators
No signup required		Varies
Works offline in browser
Reverse GST calculation (inclusive to exclusive)	Rare	Varies
Data never leaves your device

100% freeNo signupRuns in your browser

TL;DR

Free GST 2.0 calculator for India — add or remove GST at the current 0%, 5%, 18% and 40% slabs (legacy 12%/28% included for old invoices) with CGST/SGST/IGST breakdown.
Works for both GST-inclusive and GST-exclusive prices; instant, no signup.

From WOWHOW

India Business Billing Kit — 10 GST Canva Templates

Branded, GST-ready invoice templates you can edit in Canva.

₹765

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About GST Calculator

Every Indian business transaction involves a GST decision: which slab, add or reverse, CGST+SGST or IGST? Getting it wrong — even by applying CGST+SGST on an inter-state sale — can cause invoice mismatches in GSTR-2B and ITC disputes. This calculator shows every slab simultaneously — the current GST 2.0 rates and the legacy 12%/28% for older invoices and lets you toggle between add-tax and remove-tax (reverse) modes, so you see the full picture before raising an invoice or reconciling a purchase.

How It Works

In Add GST mode, the tool computes: GST Amount = Base Price × Rate / 100, and Total = Base Price + GST Amount. This is the amount you charge the buyer and collect to remit to the government. For intra-state supplies, GST splits equally: CGST = SGST = Rate/2. For inter-state, IGST = full rate.

In Remove GST mode (reverse calculation), the tool extracts the base price from a GST-inclusive total: Base = Inclusive Total / (1 + Rate/100). This is useful when you receive a GST-inclusive invoice and need to separate the tax component for your books or ITC claim.

Every slab is shown simultaneously — the current GST 2.0 rates (0%, 5%, 18%, 40%) and the legacy 12%/28% for invoices dated before 22 September 2025 — making it easy to verify the right slab without switching back and forth.

Who Is This For

A freelance consultant raising a GST invoice for a client in a different state, confirming that IGST at 18% applies rather than CGST+SGST.

A retailer receiving goods with an MRP-inclusive price, needing to extract the base price and GST component for accounting.

An accounts executive reconciling purchase invoices and verifying the GST amounts match the supplier-declared values.

A small business owner checking how the GST 2.0 move of their product from 12% to 5% (or 28% to 18%) changes the final price they should charge.

Scope note: Shows the GST 2.0 slabs (0%, 5%, 18%, 40%) plus the legacy 12%/28% rates for pre-Sept-2025 invoices. Does not cover the special 3% precious-metals rate, the transitional cess treatment retained for tobacco/pan masala, composition scheme rates, exempt supply rules, or RCM (Reverse Charge Mechanism) transactions. For precise HSN/SAC classification and applicable rate, use the HSN & SAC Code Finder tool or consult a GST practitioner.

Disclaimer: This calculator is for informational and educational purposes only and does not constitute financial, tax, or legal advice. Results are estimates based on publicly available tax slabs and formulas. Consult a qualified Chartered Accountant, tax professional, or financial advisor for guidance specific to your situation. Built and maintained by the WOWHOW Team with 14+ years of software development experience.

How to Use

Enter any amount in the input field

Toggle between "Add GST" and "Remove GST" modes

View results for every GST slab simultaneously — current and legacy

Switch between Intra-state (CGST+SGST) and Inter-state (IGST) view

Frequently Asked Questions

To add GST: GST Amount = Base Price x GST Rate / 100. Total = Base Price + GST Amount. To remove GST from inclusive price: Base = Total / (1 + GST Rate/100).

For intra-state (same state) transactions, GST is split equally between CGST (Central GST) and SGST (State GST). For inter-state transactions, IGST (Integrated GST) applies at the full rate.

Under GST 2.0 (effective 22 September 2025) India has 4 main slabs: 0% (essentials), 5% (merit rate), 18% (standard rate for most goods and services), and 40% (de-merit rate for luxury and sin goods), plus a special 3% rate for gold. The old 12% and 28% slabs were abolished — most 12% items moved to 5% and most 28% items to 18%.

If you have the GST-inclusive price, divide by (1 + GST Rate/100) to get the base price. For example, Rs 118 at 18% GST: 118 / 1.18 = Rs 100 base price.

The 28% slab no longer exists — GST 2.0 removed it on 22 September 2025. Everyday items that sat at 28% (air conditioners, TVs, cement, small cars) now attract a flat 18%, while luxury vehicles, tobacco, pan masala, and aerated drinks moved to the new 40% de-merit rate. Use the legacy 28% row only for invoices dated before the switchover.

Composition scheme dealers (turnover below Rs 1.5 crore) pay GST at reduced flat rates — 1% for traders, 5% for restaurants, 6% for service providers — instead of the standard slab rates. Composition dealers cannot issue tax invoices or charge GST separately from customers. This calculator uses standard slab rates, not composition rates.

GST is calculated on the net taxable value after deducting any pre-agreed discounts that are mentioned on the invoice. Post-sale discounts are handled through credit notes. Enter the post-discount price as the base amount in this calculator to get the correct GST on a discounted transaction.