As you know, govt has changed set off rule in GST. In new set off rule IGST will be first exhausted with IGST/CGST and SGST liability then only CGST and SGST will be utilised for CGST and SGST set off respectively.
I have created an excel to cater new set off rule, hope it may useful.
Please give your feedback and DM in case of bug. #xlsx