For freelancers & the self-employed

Quarterly tax calculator

The IRS wants your taxes as you earn, not all at once in April. Enter your income and we'll split your estimated federal tax into four calm quarterly payments — with every 1040-ES due date.

Reviewed for accuracy by [Reviewer Name], CPA · Updated for tax year 2026 · How this is calculated · Estimates pending CPA review

How the quarterly tax calculator works

When you work for yourself, no employer withholds tax from your pay. The IRS closes that gap with estimated taxes — four payments spread across the year using Form 1040-ES. This tool estimates your full-year federal liability on your self-employment income, then divides it into four equal installments so each deadline is predictable instead of a scramble.

What goes into each payment

Your estimated federal tax has two parts. The first is self-employment tax — 15.3% (12.4% Social Security up to the annual wage base, plus 2.9% Medicare, with an extra 0.9% on higher earnings) on 92.35% of your net profit. The second is federal income tax on your taxable income after the standard deduction, half of your self-employment tax, and a simplified 20% Qualified Business Income deduction. We estimate only the tax your self-employment income adds on top of any other household income, so the quarterly figure reflects your real situation rather than a flat guess. See IRS: Self-Employment Tax and IRS: QBI Deduction.

Equal payments, four fixed dates

The simplest safe approach is four equal payments. If a payment date lands on a weekend or federal holiday, it shifts to the next business day. If you had tax withheld from a W-2 job, you can subtract it here, since that withholding already counts toward your total. If your income is uneven across the year, the IRS also allows an annualized income method that matches payments to when you actually earned — a good conversation to have with a tax pro.

A calmer way to do it: the moment a client pays you, move your set-aside percentage into a separate account. When each quarterly date arrives, the money is already waiting. Our self-employed tax calculator gives you that percentage, and our business banking guide covers accounts that auto-split every deposit.

Frequently asked questions

Who has to pay quarterly estimated taxes? If you expect to owe $1,000 or more for the year after any withholding, the IRS generally expects quarterly payments to avoid an underpayment penalty. See IRS: Estimated Taxes.

When are the 2026 payments due? April 15, 2026; June 15, 2026; September 15, 2026; and January 15, 2027. The "January" payment is the fourth installment for the prior tax year.

What if I miss one? You may owe a modest underpayment penalty, calculated like interest on the shortfall for the days it was late. Paying as soon as you can keeps it small — missing a deadline is not a catastrophe, just something to fix quickly.

Related tools: Self-employed tax calculator · 1099 vs W-2 calculator · Home office deduction calculator · Tax deadlines guide

Educational estimate — not tax advice. This tool gives a rough approximation using simplified 2026 federal rules (standard deduction, a simplified QBI deduction capped at 20% of taxable income, and self-employment tax including Additional Medicare). It does not model QBI phase-outs, itemized deductions, credits, the annualized-income installment method, or state taxes. Tax figures are current-year estimates pending final CPA review and may change. Your actual liability depends on your specific situation and is not a substitute for a CPA, EA, or the IRS. Everything is calculated entirely in your browser — nothing you type is stored or sent anywhere.