Business tax
Tax Calculators for Self-Employed Operators and Small Businesses
Know what is not really yours yet.
Estimate tax reserves, quarterly payments, deduction caution, S-corp savings, and owner-salary planning with visible assumptions and plain-English next steps.
What tax problem are you trying to avoid?
What are you trying to figure out?
How much should I set aside for taxes?
Self-Employed Tax Calculator
I need to pay quarterly taxes.
Quarterly Tax Estimate
I missed or underpaid a quarter.
Quarterly Tax Catch-Up
My income is irregular.
Irregular Income Tax Reserve
I have W-2 and 1099 income.
Mixed W-2 + 1099 Tax Planner
Can I deduct this?
Dangerous Deduction Checker
What deductions should I review?
Self-Employed Deduction Finder
Is S-corp worth it?
LLC vs S-Corp
How much could S-corp save?
S-Corp Tax Savings
What should I pay myself?
Reasonable Salary Planner
Are my records good enough?
Deduction Documentation Scorecard
Featured calculators
Run the uncomfortable tax math
Tax Reserve Health Score
Find out whether your tax money is actually protected.
Score whether the business is reserving enough for taxes based on income, expenses, withholding, prior payments, irregular income, state assumptions, and upcoming deadlines.
Run calculatorSelf-Employed Tax Calculator
Know what is not really yours yet.
Estimate federal self-employment tax, income-tax reserve, and monthly or quarterly set-asides before gross revenue gives you false confidence.
Run calculatorQuarterly Tax Estimate Calculator
Make tax payments boring.
Estimate quarterly tax planning payments using current income, prior payments, withholding, uneven income, and safe-harbor assumptions.
Run calculatorDangerous Deduction Checker
Keep the deduction. Lose the panic.
Flag expenses that may need stronger records, clearer business-use allocation, capitalization review, or a more conservative treatment.
Run calculatorLLC vs S-Corp Calculator
Do not form an entity around a fantasy spreadsheet.
Compare LLC/default taxation and S-corp election planning after reasonable salary, payroll costs, filing costs, state costs, and admin time.
Run calculatorS-Corp Tax Savings Calculator
Savings are only savings after the admin is paid for.
Estimate possible S-corp savings after reasonable salary, payroll taxes, payroll service, bookkeeping, filing, state costs, and admin time.
Run calculatorReasonable Salary Planner
Pay yourself like an operator, not a loophole.
Build a practical owner-salary planning range for S-corp modeling using role, time, skill, responsibility, comparable pay, and business economics.
Run calculatorThe uncomfortable tax math
Most tax stress starts before tax season. It starts when gross revenue looks spendable, deductions are remembered instead of documented, quarterly payments are guessed, and S-corp savings are modeled without payroll, salary, filing, state, and admin costs.
Tax tracks
Mistakes and field guides
Why Gross Revenue Is Not Take-Home Pay
Revenue is not take-home pay.
Show why self-employed people feel richer than they are when taxes, expenses, reserves, and slow months are not separated.
How Much Should I Set Aside for Taxes?
Know what is not really yours yet.
Turn self-employed income into a practical tax reserve habit.
What If I Missed a Quarterly Tax Payment?
Being behind is a problem. Guessing is worse.
Help self-employed operators quantify the gap and rebuild the payment rhythm.
Quarterly Taxes With Irregular Income
Do not average this blindly.
Show why high-income months need immediate tax reserve discipline.
W-2 and 1099 Tax Planning
Two income streams need one tax plan.
Help mixed-income workers compare extra withholding and quarterly payments.
Risky Tax Deductions to Review Carefully
Keep the deduction. Lose the panic.
Help operators spot documentation and mixed-use issues before filing season.
Mixed-Use Business Expenses
Business use and personal use need different treatment.
Explain why mixed-use expenses need allocation instead of guesswork.
How to Document Business Expenses
The record matters as much as the expense.
Turn receipts into records that explain the business story.
Is an S-Corp Worth It at $80k, $100k, or $150k?
The savings number is not the whole decision.
Stress-test S-corp thresholds instead of trusting one exciting screenshot.
Checklists and templates
Weekly Tax Reserve Checklist
Move the tax money before it starts looking spendable.
Quarterly Tax Review Checklist
A quarter should end with numbers, not guessing.
Business Expense Documentation Note Template
Write the business reason while you still remember it.
S-Corp Readiness Checklist
Make sure the admin is worth the savings.
Questions to Ask a CPA After Running an S-Corp Calculator
Use the calculator to ask better questions.
All tax calculators
Self-Employed Tax Calculator
Know what is not really yours yet.
Estimate federal self-employment tax, income-tax reserve, and monthly or quarterly set-asides before gross revenue gives you false confidence.
Quarterly Tax Estimate Calculator
Make tax payments boring.
Estimate quarterly tax planning payments using current income, prior payments, withholding, uneven income, and safe-harbor assumptions.
Tax Reserve Health Score
Find out whether your tax money is actually protected.
Score whether the business is reserving enough for taxes based on income, expenses, withholding, prior payments, irregular income, state assumptions, and upcoming deadlines.
Quarterly Tax Catch-Up Calculator
Being behind is a problem. Guessing is worse.
Estimate how much to catch up after a missed or low quarterly tax payment, then build a forward reserve plan.
Mixed W-2 + 1099 Tax Planner
Two income streams need one tax plan.
Estimate how W-2 withholding and self-employment income interact so users do not overpay, underpay, or guess.
Irregular Income Tax Reserve Planner
Seasonal income needs seasonal reserves.
Create a tax reserve plan for freelancers, consultants, creators, and businesses with uneven income.
Self-Employed Deduction Finder
Find the expenses hiding in plain sight.
Review common self-employed expense categories and see which ones may deserve documentation, business-use allocation, or professional review.
Dangerous Deduction Checker
Keep the deduction. Lose the panic.
Flag expenses that may need stronger records, clearer business-use allocation, capitalization review, or a more conservative treatment.
Deduction Documentation Scorecard
The record matters as much as the expense.
Score how well an expense or category is documented before tax season turns it into a memory test.
LLC vs S-Corp Calculator
Do not form an entity around a fantasy spreadsheet.
Compare LLC/default taxation and S-corp election planning after reasonable salary, payroll costs, filing costs, state costs, and admin time.
S-Corp Tax Savings Calculator
Savings are only savings after the admin is paid for.
Estimate possible S-corp savings after reasonable salary, payroll taxes, payroll service, bookkeeping, filing, state costs, and admin time.
S-Corp Break-Even Stress Test
Find the point where complexity starts paying for itself.
Stress-test S-corp savings against lower profit, higher salary, higher state costs, payroll cost, filing cost, and admin time.
Reasonable Salary Planner
Pay yourself like an operator, not a loophole.
Build a practical owner-salary planning range for S-corp modeling using role, time, skill, responsibility, comparable pay, and business economics.
Kefiw tax methodology
Kefiw tax tools use visible assumptions, source checks, conservative scenarios, and "what this tool does not do" sections because tax decisions are damaged by hidden inputs and stale certainty.
Read the Tax Source Verification Policy