Calculator Input
Enter your values below. The form uses a three column layout on large screens, two columns on smaller screens, and one column on mobile.
Example Data Table
Use these example scenarios to understand how the calculator behaves across different self-employed business sizes.
| Scenario | Business Income | Expenses | Net Profit | Total Tax | Quarterly Payment | After Tax Income |
|---|---|---|---|---|---|---|
| Freelance Designer | $85,000.00 | $18,000.00 | $67,000.00 | $15,545.45 | $2,136.36 | $53,454.55 |
| Independent Consultant | $145,000.00 | $35,000.00 | $110,000.00 | $29,868.25 | $2,967.06 | $86,131.75 |
| Small Agency Owner | $240,000.00 | $92,000.00 | $148,000.00 | $44,850.33 | $3,712.58 | $113,149.67 |
Formula Used
These formulas keep the calculator transparent. You can change the tax percentages to match your own planning assumptions.
1. Net Business Profit
Start with gross receipts and subtract ordinary business expenses.
Net Profit = Business Income − Business Expenses2. Net Earnings for Self Employment Tax
This estimate applies the common 92.35% adjustment to net profit.
Net Earnings for SE Tax = Net Profit × 0.92353. Self Employment Tax
Apply your selected self-employment tax rate to adjusted net earnings.
Self Employment Tax = Net Earnings for SE Tax × SE Tax Rate4. Deductible Half of Self Employment Tax
Half of the self-employment tax is treated as an income adjustment.
Deductible Half SE Tax = Self Employment Tax ÷ 25. Adjusted Income
Other income is added. Then selected deductions reduce the amount.
Adjusted Income = Net Profit + Other Income − Half SE Tax − Retirement − Health Insurance6. Qualified Business Income Deduction
This planning estimate reduces taxable income using your QBI rate.
QBI Deduction = max(Net Profit − Half SE Tax − Retirement − Health Insurance, 0) × QBI Rate7. Taxable Income
Taxable income subtracts standard, extra, and QBI deductions.
Taxable Income = max(Adjusted Income − Standard Deduction − Additional Deductions − QBI Deduction, 0)8. Total Tax and Payment Estimates
Federal, state, and self-employment taxes combine into the total tax estimate.
Total Tax = Self Employment Tax + Federal Income Tax + State Income Tax Quarterly Payment = max(Total Tax − Estimated Payments, 0) ÷ 4How to Use This Calculator
Step 1
Enter annual business income before expenses. Add only revenue earned through self-employed activity.
Step 2
Enter business expenses that directly support your work. Keep personal spending separate for cleaner estimates.
Step 3
Add other income, deductions, retirement contributions, and health insurance adjustments if you want a fuller picture.
Step 4
Use the tax rate fields to match your planning model. These are editable because rates and rules vary.
Step 5
Click calculate. Review the result cards, step table, and chart to see how each value affects the total.
Step 6
Download the results as CSV or PDF for budgeting, tax meetings, or quarterly payment tracking.
Frequently Asked Questions
1. What does this calculator estimate?
This calculator estimates net profit, self-employment tax, income tax, state tax, quarterly payments, and after tax income using your adjustable assumptions.
2. Why is the self-employment tax based on 92.35%?
The calculator applies the common 92.35% adjustment before multiplying by the self-employment tax rate. This improves planning realism for many self-employed scenarios.
3. Can I use custom tax rates?
Yes. Federal, state, self-employment, and qualified business income rates are editable. That helps you model different locations, years, and planning assumptions.
4. Does this replace a professional tax return?
No. This is a planning tool, not filing software. Use it for estimation and budgeting, then confirm final tax treatment with a qualified professional.
5. Should I include all revenue in business income?
Include revenue earned from your self-employed activity. Put unrelated earnings into the other income field when you want a broader annual estimate.
6. What are estimated payments?
Estimated payments are tax amounts already paid during the year. Entering them helps the calculator estimate balance due or a possible refund.
7. Why does the quarterly payment differ from total tax?
The quarterly figure uses the remaining balance after subtracting estimated payments. It helps you plan upcoming installments rather than restating the full annual tax.
8. Can this help with pricing decisions?
Yes. After tax income, monthly reserve, and effective tax rate can help you set prices, savings targets, and cash flow buffers more confidently.