For 2017 and 2018, the maximum you can contribute to all of your traditional and Roth IRAs is the lesser of:
$5,500 ($6,500 if you're age 50 or older), or
100% of earned income or compensation
The maximum a self-employed person or business owner can contribute to an employee's SEP IRA is the lesser of:
25% of the employee's compensation,
or $54,000 for tax year 2017 and $55,000 for tax year 2018