India has four GST slab rates: 5%, 12%, 18%, and 28%. Different goods and services fall under different slabs. Essential items typically have lower rates (0% or 5%), while luxury goods have higher rates (28%). Some items like petroleum products, alcohol, and electricity are not covered under GST.

CGST (Central GST) and SGST (State GST) are levied on intrastate transactions (within the same state). Each represents half of the total GST. IGST (Integrated GST) is levied on interstate transactions (between different states) and is equal to the full GST rate. CGST goes to the Central Government while SGST goes to the State Government.

Yes, you can use this calculator for reverse charge calculations. Simply enter the transaction amount and select the appropriate GST rate. The GST amount calculated will be the same whether it's charged forward or reverse. Under reverse charge, the recipient pays the tax instead of the supplier.