GST Calculator
A premium GST Studio that handles every everyday GST scenario: add GST to a base price (exclusive), extract GST from a final bill (inclusive), reverse-calculate the taxable value from a selling price, or build a full multi-line invoice with per-item GST rates, discounts, shipping and round-off. Automatic CGST + SGST splitting for intra-state supplies and IGST for inter-state supplies, with invoice-style breakdowns, donut charts, smart insights, PDF/CSV export and print. Every calculation runs entirely in your browser — your financial data never leaves your device.
Calculation Mode
GST Rate
Supply Type
🔒 All calculations happen entirely inside your browser. Your financial information is never uploaded or stored on our servers.
Taxable Value
₹10,000
GST Amount
₹1,800
Final Amount
₹11,800
Effective Rate
15.3%
Tax Breakdown
GST Exclusive · Intra-state| Taxable Amount | ₹10,000 |
| GST @ 18% | ₹1,800 |
| CGST | ₹900 |
| SGST | ₹900 |
| Grand Total | ₹11,800 |
Tax Split
CGST
₹900
SGST
₹900
IGST
₹0
Intra-state supply — the total GST is split equally between CGST (central) and SGST (state).
Smart Insights
- Intra-state supply — the 18% GST splits into CGST ₹900 + SGST ₹900.
- GST contributes ₹1,800 to the final ₹11,800 — an effective 15.25% of the final price.
- GST is added on top of the base price — the customer pays ₹11,800, of which ₹1,800 is tax.
GST Basics — Know Before You Calculate
What is GST?
Goods and Services Tax is a value-added tax levied on most goods and services sold in India. It replaced a tangle of old taxes (VAT, service tax, excise, octroi) with one unified tax at the point of supply.
Inclusive vs Exclusive
Exclusive means GST is added on top of the base price (the seller quotes ₹10,000 + 18% GST = ₹11,800). Inclusive means the quoted price already contains the tax (₹11,800 including GST — the taxable value is ₹10,000).
CGST & SGST
For supplies within the same state (intra-state), the total GST is split equally: half goes to the central government (CGST) and half to the state government (SGST).
IGST
For supplies between different states (inter-state) and imports, the full GST is collected as IGST by the central government, which then distributes the state portion — keeping the tax base neutral across states.
GST Slabs
India uses multi-tier rates: 0% (essentials), 3% (some gold & jewellery items), 5% (staples, transport), 12% (processed food, phones), 18% (most services, standard goods) and 28% (luxury and sin goods, plus cess).
Common Mistakes
Adding GST to an already-inclusive price (double-taxing), using the wrong slab for a product, forgetting to split CGST/SGST on intra-state invoices, and ignoring discount calculations before applying tax. This calculator handles all of it.
HSN / SAC Codes
Every GST invoice needs a code: HSN for goods (e.g. 8471 for computers) and SAC for services (e.g. 9995 for software). Look them up by keyword or code and apply the suggested slab in one tap — rates are indicative, so verify against official notifications before filing.
How to Use This Calculator
Choose a mode — Exclusive, Inclusive, or Reverse — then enter the base amount and pick a rate slab (or a custom rate). Toggle intra-state or inter-state to get the correct CGST+SGST or IGST split. For multi-item invoices, switch to Bulk mode, add a row per line item with its own rate and discount, and let the calculator total the invoice with round-off applied at the end.
Common Use Cases
Freelancers and small businesses quoting a GST-inclusive price to a client and needing the taxable value for their own books; shop owners building a quick multi-item bill with per-item GST rates and a shipping charge; anyone checking whether an invoice they received has been taxed correctly under the right CGST/SGST or IGST split.
Calculation Mode
GST Rate
Supply Type
🔒 All calculations happen entirely inside your browser. Your financial information is never uploaded or stored on our servers.
ForgePlug GST Invoice
GST Studio · calculator & invoice breakdown
Generated 15 Sept 2026
₹11,800
GST Exclusive
All calculations ran entirely in your browser — no financial data was uploaded or stored. GST rates follow standard Indian slabs; verify against your jurisdiction before filing.
forgeplug.com/tools/gst-calculator
Frequently Asked Questions
Everything you need to know about GST calculations
How do I calculate GST on a price?
What is the difference between CGST, SGST and IGST?
What are the standard GST rates in India?
What is reverse GST calculation?
What are HSN and SAC codes?
How is round-off handled on invoices?
Is my financial data stored or uploaded?
Guides & Articles
Learn how to get the most out of this tool with our in-depth guides.
What a Professional Invoice Must Include (and What to Skip)
An invoice is a legal record as much as a payment request. Here's the field-by-field breakdown of what belongs on one and what delays payments.
GST Inclusive vs Exclusive Pricing Explained
Is the price on the tag before or after tax? Here's how inclusive and exclusive GST pricing differ, and which one your invoice should use.
Free Invoice Generator: Create Invoices Online Without Uploading Anything
Sending a professional invoice shouldn't require an account or a server that stores your client data. Here's how a browser-only invoice generator works.
Tool Overview
A closer look at GST Calculator — how it works, who it's for, and where it fits in your workflow.
GST appears in almost every Indian transaction, but it's easy to get the math wrong: is GST included in that MRP or added on top? The GST Calculator handles every everyday scenario — add GST to a base price (exclusive mode), extract GST from a final bill (inclusive mode), or reverse-calculate the taxable value when you only know the selling price. Whatever you're computing, the tool returns the base amount, GST amount, and final total in one view.
For invoices, the calculator acts like a mini billing studio. Build a multi-line invoice with per-item GST rates, add discounts and shipping, apply round-off, and the tool produces an invoice-style breakdown with automatic CGST + SGST splitting for intra-state supplies and IGST for inter-state ones. The donut chart and smart insights make the tax composition visible at a glance, and PDF/CSV export plus print support mean you can produce a clean, shareable statement without a spreadsheet.
Financial documents are sensitive, so every calculation runs locally in your browser. Nothing you compute — prices, rates, invoice details — is uploaded anywhere, and there's no account to create.
Key Features
Everything you get with this tool, at a glance.
Inclusive, Exclusive & Reverse
Add GST, extract it from a bill, or reverse-calculate taxable value.
Multi-Line Invoices
Per-item GST rates with discounts, shipping, and round-off.
CGST/SGST/IGST Splits
Automatic intra-state and inter-state tax distribution.
Invoice Breakdown Charts
Donut charts and insights that visualize the tax composition.
PDF, CSV & Print
Export a clean invoice-style statement in multiple formats.
Private & Free
All calculations are client-side; no data leaves your device.
How to Use GST Calculator
Get from zero to done in four quick steps — no account, no learning curve.
Choose a mode
Pick exclusive (add GST), inclusive (extract GST), or reverse (find taxable value).
Enter the amount & rate
Type the price and GST rate (5%, 12%, 18%, 28%, or any custom rate).
Review the breakdown
Read the base amount, GST, total, and CGST/SGST or IGST split.
Export or print
Download a PDF/CSV statement or print the invoice-style summary.
Practical Examples
Real input and output pairs so you know exactly what to expect.
18% GST on ₹10,000
Input
Exclusive · ₹10,000 · 18%
Output
GST ₹1,800 · Total ₹11,800 (CGST ₹900 + SGST ₹900)
Extract GST from ₹11,800 bill
Input
Inclusive · ₹11,800 · 18%
Output
Base ₹10,000 · GST ₹1,800
Inter-state IGST
Input
Invoice ₹50,000 · 12% · Maharashtra → Karnataka
Output
IGST ₹6,000 (no CGST/SGST split)
Guides & Articles
Learn how to get the most out of this tool with our in-depth guides.
What a Professional Invoice Must Include (and What to Skip)
An invoice is a legal record as much as a payment request. Here's the field-by-field breakdown of what belongs on one and what delays payments.
GST Inclusive vs Exclusive Pricing Explained
Is the price on the tag before or after tax? Here's how inclusive and exclusive GST pricing differ, and which one your invoice should use.
Free Invoice Generator: Create Invoices Online Without Uploading Anything
Sending a professional invoice shouldn't require an account or a server that stores your client data. Here's how a browser-only invoice generator works.
Part of Finance & Calculations, Business Essentials
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