I tried calling the IRS to ask them directly, but the wait time on the phone is too great. As a self employed person, I basically just need to understand exactly what I owe in income tax and self employment tax. Please let me know if I've got this right. Paychecks for the year 2012: $30,000 1. Federal income tax: Standard deduction: $5,950 Personal exemption: $3,800 Income to be taxed federally: $20,250. 2. Self employment tax: 92.35% x $30,000 = $27,705 Business expenses = $5,950 (standard deduction) Income taxed by the self employment tax: $21,755. 13.3% = $2,893 for self employment tax (social security and medicare) Then... to amend part 1: 0.5 x $2,893 = $1,446.50 $1,446.50 further deduction for federal income tax. New total to be federally taxed: $18,803.50 $2,396 owed in federal income tax. $2,893 for self employment tax. Total: $5,289. Effective total tax rate: 17.6%. Is this right? Thanks!