GST
Calculating GST correctly is essential for accurate invoicing. There are two common scenarios: GST-exclusive pricing and GST-inclusive pricing.
When your listed price does not include GST, tax is added on top:
GST Amount = Taxable Value × (GST Rate / 100)
Total = Taxable Value + GST Amount
Example: A service priced at ₹10,000 with 18% GST → GST = 10,000 × 0.18 = ₹1,800. Total payable = ₹11,800.
When your listed price already includes GST, you need to extract the tax component:
Taxable Value = Total Price / (1 + GST Rate / 100)
GST Amount = Total Price − Taxable Value
Example: A product sold at ₹11,800 (inclusive of 18% GST) → Taxable Value = 11,800 / 1.18 = ₹10,000. GST Amount = ₹1,800.
For sales within the same state, the total GST is split equally between CGST and SGST. For sales between two different states, the full amount is charged as IGST instead.
Doing this manually for every invoice is time-consuming and error-prone. Our GST invoice generator applies these exact formulas automatically using deterministic JavaScript calculations.