Use this Self-Employment Tax Calculator to estimate your tax bill or refund. This tool uses the latest information provided by the IRS including annual changes and those due to tax reform. Gather your 2020 tax documents including 1099s, business receipts, bank records, invoice payments, and related documents to fill in the drop down sections. Explanations for each question are provided below in the chart. If you have questions about your self-employment taxes a Tax Pro can help.