Side Hustle Income Tax Calculator

Anyone with a main job who's picked up freelance, gig, or 1099 work on the side and wants to know how much of that extra money they'll actually keep after tax. The answer surprises people, because side income is taxed differently than their first dollar of salary.

Your side hustle doesn't start in the 10% bracket — it stacks on top of your main job's income, so it's taxed at your marginal rate (the bracket your last dollar lands in). This calculator finds the extra tax by comparing your tax bill with and without the side income.

If the side work is self-employment, it also owes the 15.3% self-employment tax (Social Security + Medicare), which employees don't pay on their own. That's why 1099 income carries a noticeably higher effective rate.

Turn off the self-employment toggle if your side income is a second W-2 job — then only the extra income tax applies, because Social Security and Medicare are already withheld by that employer. Leave it on for freelance, gig, or contractor income.

Federal only, using 2026 figures that still need verification against IRS and SSA sources. It excludes state tax, the 0.9% Additional Medicare Tax, and any credits or deductions beyond the standard deduction. Set aside a bit more than shown to be safe, and confirm with a tax professional.