Quarterly estimated tax calculator
Enter your net profit for the year. The calculator adds the 2026 self-employment tax and the extra federal income tax, then divides by four so you can set money aside each quarter.
Enter your net profit to see your estimate.
Estimate for 2026
- Net earnings (92.35 % of profit)
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- Deductible half of the self-employment tax
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- Exempt below $400 of net earnings
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An estimate, not tax advice
This doesn’t include the 20 % qualified business income (QBI) deduction, state or local income tax, other credits or deductions, or any tax you already paid through withholding or estimated payments. The quarterly figure is the yearly total divided by four. Your due dates depend on your situation, so check the IRS page below.How it’s calculated
- Base
- Net profit × 92.35 %
- Social Security
- 12.4 % of the base, up to $184,500 minus your W-2 wages
- Medicare
- 2.9 % of the base, no limit
- Additional Medicare
- 0.9 % of the base above $200,000 (single or head of household), $250,000 (married filing jointly), or $125,000 (married filing separately), counting your W-2 wages first
- Income tax effect
- Federal income tax with the profit minus federal income tax without it, using the standard deduction and 2026 brackets
Official figures
The 2026 Social Security wage base is $184,500, and the self-employment rates are 12.4 % and 2.9 %. Verified on October 8, 2026. Source: IRS, Topic no. 751, Social Security and Medicare withholding rates.
The additional Medicare thresholds come from IRS, Topic no. 560, Additional Medicare Tax. Estimated tax payments: IRS, Estimated taxes (small businesses and self-employed), verified on October 8, 2026.
How to use it
- Enter your net profit from self-employment for the year (Schedule C, line 31).
- If you also have W-2 wages for the same year, enter them. They use up part of the Social Security base.
- Choose your filing status, since it sets the Additional Medicare threshold and the standard deduction.
- Read the self-employment tax, the deductible half, the income tax effect, and the quarterly estimate.
- Copy the result or a link that opens the calculator with your numbers.
Frequently asked questions
How do I work out a quarterly estimated tax amount?
Estimate the full year's self-employment tax and the extra income tax on your profit, then divide by four. At $80,000 of net profit the yearly total is $18,830.24, or $4,707.56 per quarter.
Is the quarterly figure the amount due to the IRS?
Not necessarily. This is a planning amount. What you must pay and when depends on your withholding, your prior-year tax, and the IRS safe-harbor rules, so check the IRS estimated taxes page.
Why quarters
Self-employed people usually have no employer withholding taxes from each payment, so the IRS expects them to pay during the year through estimated payments. Setting aside a fixed share of every invoice makes those payments easier to meet.
The math at $80,000 of net profit
The base is $73,880, and self-employment tax comes to $11,303.64. Half of that tax lowers your income, which leaves an extra federal income tax of $7,526.60. The yearly total is $18,830.24, so each quarter is $4,707.56.
What the figure does not cover
It leaves out state tax, the 20 % qualified business income deduction, and any credits. Your due dates are on the IRS estimated taxes page, not in this calculator.
Updated on October 8, 2026