Free Online GST Calculator for India

Calculate CGST, SGST, IGST amounts and net/gross prices instantly across all standard GST slabs (5%, 12%, 18%, 28%).

Interactive GST Calculator Tool

Use the live Gopustak web application for dynamic real-time invoice generation and automatic tax computation.


Open Live GST Invoice Calculator

How GST Calculation Formula Works

1. GST Exclusive Calculation (Add GST)

GST Amount = (Amount × GST Rate%) / 100
Net Total = Amount + GST Amount

2. GST Inclusive Calculation (Remove GST)

GST Amount = Amount - [Amount × 100 / (100 + GST Rate%)]
Pre-Tax Base Amount = Amount - GST Amount