What a GST tax invoice must show
Rule 46 of the CGST Rules lists the details a tax invoice must carry. In plain words: your name, address and GSTIN; an invoice number that runs in one series for the financial year, with no more than 16 characters; the date of issue; and the buyer’s name, address and GSTIN if the buyer is registered.
For each item it needs a description, the HSN code for goods or SAC code for services, the quantity and unit, the value, any discount and the taxable value after that discount. It also needs the GST rate and the tax amount split into CGST and SGST, or IGST, and the place of supply with the state name when the sale crosses a state border.
Finally, the invoice should say whether tax is payable under reverse charge, and carry a signature of the supplier or an authorised person. If an unregistered buyer’s invoice is ₹50,000 or more, include the buyer’s address and state as well. The fields in this generator cover these points; the reverse charge line can go in the notes box when it applies.
CGST and SGST, or IGST
The split depends on where the supply happens. When your state and the place of supply match, half the tax goes to the centre as CGST and half to the state as SGST. When they differ, the whole tax goes in as IGST. The generator compares the two state selections and switches the columns for you, so an 18% line shows 9% plus 9% within the state and 18% IGST outside it.
Different items on one invoice can carry different rates. The tax-by-rate table groups the taxable value under each rate, which mirrors how the figures are reported in GSTR-1.
Rounding and the amount in words
Each line is worked out to the paisa. The grand total is then rounded to the nearest rupee, with 50 paise and above going up, and the difference appears on its own round-off line so your books still balance. The amount in words uses lakh and crore, as Indian invoices normally do.
E-invoicing is a separate step
Businesses whose turnover crosses the e-invoicing limit, currently ₹5 crore, must report each B2B invoice to the Invoice Registration Portal and print the IRN and signed QR code it returns. This free generator does not connect to the portal and does not create an IRN. If e-invoicing applies to you, raise those invoices through the IRP directly or through billing software linked to a GST Suvidha Provider.
If you bill every day, an ERP with GST billing keeps items, HSN codes, rates and number series together and can raise e-invoices from the same screen.