GST Calculator Inclusive and Exclusive
Add or remove GST from an amount. See CGST, SGST or IGST split for 5%, 12%, 18% and 28% so invoices stay accurate.
Calculation Results
Related Calculators
What is GST Calculator?
Compute Indian Goods and Services Tax seamlessly for business invoices, freelance billings, and retail purchases. You can add GST to a net base price or extract GST from a gross retail total across statutory 5%, 12%, 18%, and 28% tax slabs. The calculator automatically divides the tax into Central GST (CGST) and State GST (SGST) for local state transactions or Integrated GST (IGST) for inter-state commercial supplies, ensuring accurate financial ledger accounting in rupees (₹).
How to Use GST Calculator in 4 Easy Steps
Step 1
Enter the base invoice amount or gross retail price in rupees (₹).
Step 2
Choose whether to Add GST (exclusive) or Remove GST (inclusive).
Step 3
Select a standard GST rate slab (5%, 12%, 18%, 28%) or enter a custom rate.
Step 4
Review the itemized breakdown showing Net Amount, Total GST, CGST, SGST, and Final Gross Total.
Honest Technical Specifications & Limits
Supported Slabs
0%, 3%, 5%, 12%, 18%, 28%, and custom decimal tax percentages.
Tax Splitting
Automatic 50/50 division between CGST and SGST for domestic supply.
Precision
Rounded to two decimal places for compliance with accounting ledgers.
Privacy First: 100% Client-Side In-Browser Processing
100% In-Browser Local Execution. GST Calculator operates directly inside your browser memory using client-side JavaScript and WebAssembly. Your data is never transmitted over the internet or logged on remote servers. You can open Developer Tools (F12) Network tab to verify zero outbound network calls.
Verify it yourself: Open your browser's Developer Tools (F12 or Inspect), switch to the Network tab, and perform your action. You will observe zero outbound data uploads — your data never leaves your computer.
Popular Real-World Use Cases
B2B & Freelance Invoicing
Add 18% GST to software consulting, digital marketing, or design service quotes before issuing tax invoices.
Retail MRP Price Extraction
Remove 12% or 18% inclusive GST from retail consumer items to identify the vendor pre-tax manufacturing cost.
Quarterly GSTR-1 & 3B Reconciliation
Double-check taxable supply values and input tax credit numbers when filing quarterly GST tax returns.
Calculations, Formulas & Practical Examples
GST Calculation Formula
For GST-inclusive prices, Base Cost = (Gross Price * 100) / (100 + GST Rate%).
Adding 18% GST Example
Product net price of $1,000 with standard 18% tax tier.
Removing 12% GST Example
Invoice total of $560 including 12% GST tax rate.