Twelve free calculators for what freelancers, gig workers, and small business owners owe the IRS, and what an LLC or S-corp actually costs and saves.
This page is for freelancers, gig workers, and small business owners figuring out what they actually owe the IRS, and whether an LLC or S-corp election changes that number enough to be worth the paperwork.
Start with the Self-Employed Tax Estimator for a first read on your total federal and self-employment tax, then the Quarterly Tax Calculator so you know what is due and when. If you're deciding on a business structure, run Sole Proprietor vs LLC and the S-Corp Tax Savings Calculator using your own profit and state, before paying anyone to form an entity.
What will I owe in self-employment and federal tax this year?
Line-by-line Schedule SE worksheet for self-employed filers.
What do I owe the IRS this quarter, and when is it due?
What does my state actually charge to form and keep an LLC?
Compare cost and self-employment tax side by side, using your own profit and state.
Printable worksheet to bring your S-corp numbers to your CPA.
Would electing S-corp status actually save me money?
Did I underpay my estimated taxes, and what's the penalty?
What will it actually cost to form and start my LLC?
What rate should I charge to hit my take-home goal?
What do I owe on DoorDash, Uber, Instacart, and other gig income?
What does Uber or Lyft actually pay me per hour after expenses?
Related tools
What deductions am I probably missing?
When is my next tax deadline?
If your income is irregular quarter to quarter, a flat one-quarter-of-last-year estimate can be wrong in either direction. The IRS's own safe-harbor rule, in Form 2210's instructions, lets you avoid a penalty by paying at least 90 percent of this year's actual tax or 100 percent of last year's (110 percent if last year's adjusted gross income was over $150,000), and the Underpayment Penalty Calculator checks your actual numbers against both tests instead of assuming one applies.
How we source our numbers: every calculator on this page uses current government or published-standard figures, not a guess. The full method for each one, and how we correct a number when it changes, is on our methodology page; our sourcing and correction rules are on our editorial policy page. Reviewed September 2026.
Pay against the IRS safe-harbor test that fits your situation (see above) rather than a flat quarter split, and recheck with the Quarterly Tax Calculator each time your income moves meaningfully.
Self-employment tax is 15.3 percent (Social Security plus Medicare) on net self-employment earnings, with the Social Security portion capped at the annual wage base ($176,100 for 2025, adjusted annually per the Schedule SE instructions). The Self-Employed Tax Worksheet walks the Schedule SE math line by line against your own numbers.
It depends on your state, your reasonable-salary requirement, and added payroll and filing costs, which is exactly why we built a calculator instead of quoting one number. Run S-Corp Tax Savings against your own profit before paying for the election; the S-Corp Savings Worksheet is built to bring straight to a CPA.
The IRS can charge an underpayment penalty, calculated on Form 2210. The Underpayment Penalty Calculator estimates that penalty, and the Quarterly Tax Calculator shows your next due date before you miss another one.