The Excess Concessional Contributions are counted as personal assessable income taxed at the marginal tax rate. Learn more from the ATO

LodgeiT has a worksheet to help with concessional and non-concessional contributions tax.

Fill via "Estimate" page

Scroll through Division 293, make sure to toggle "Yes" the "Show Division 293 tax?"

Then, press the "Edit" > "Additional tax on concessional contributions (Division 293)"