In this video I'm talking about the Solo Roth 401k deduction worksheet found in IRS publication 560. The calculation worksheet is for the contributions to the Solo Roth 401k and include pre-tax contributions based on your self employment income.
The Solo Roth 401k calculation is the maximum pre-tax deduction with maximizing the direct contributions to your Solo Roth 401k. There are multiple ways to calculate contributions to your Solo 401k including both the Roth and traditional sides of your retirement plan.
Here is the link to the Solo Roth 401k worksheet in IRS Publication 560.