Freelancer quarterly estimated tax calculator · 2026

What do you owe the IRS on January 15?

For US sole proprietors and 1099 contractors. Get the minimum that avoids a penalty and your full bill. Every step of the math is shown below the result. Nothing is stored.

Same tax logic as retn's bookkeeping engine, checked against IRS worksheets and an independent open-source tax model.

Net profit so far this year (income minus business expenses) Cash basis: money actually received minus expenses actually paid. As of date Used to project the full year. Defaults to today. Filing status State State figure is a rough flat-rate estimate. Estimated tax already paid this year (federal) Estimated tax already paid this year (state) W-2 federal withholding this year, if any From a day job or spouse's job (if filing jointly). Last year's total federal tax (line 24 of your 2025 Form 1040) Often lowers your minimum a lot. Enter 0 if you owed no tax last year. Last year's AGI was over $150,000 ($75,000 if married filing separately)

Want this computed from your actual invoices, every quarter?

retn is a bookkeeper that works by email. Cc a private address on your invoices, forward receipts and payout emails, and get monthly books, quarterly estimates like this one, and a Schedule C packet in January. No bank connection, no app.

Try it: forward one invoice or receipt to try@in.retn.ai. You'll get a reply in a few minutes.

Notes

This calculator assumes all income is self-employment income, the standard deduction, and no dependents or credits. It includes the 20% qualified business income (QBI) deduction with its 2026 limits (capped at 20% of taxable income, phased out at higher incomes, $400 minimum) and the 0.9% Additional Medicare Tax. Above the QBI income threshold it assumes a service business (consulting, design, writing, etc.), which gives a slightly higher, more cautious estimate. It ignores state brackets and local taxes. It is an estimate, not tax advice.