How much you can contribute is NOT based on earned income, it is "taxable compensation" as defined in IRS Pub 590A: https://www.irs.gov/publications/p590a#en_US_2019_publink1000230355
Which is basically the amount of the net earned income minus half the SE tax that is taxable after all deductions.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
