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Calculators

Free tools built by the CPA who prepares the returns. Each one lists the rules and figures it uses.

All 12 calculators

Most used

S-Corp vs. Sole Proprietor ›1099 Estimated Tax Planner ›Withholding Checkup ›
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Models

Excel workbooks for reporting and tax analysis. Licensed per user or firm; you own your copy.

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What’s inside

21 tabs, 28,550 formulas (FRP) ›§1374 and LIFO recapture (C→S) ›Pre- and post-2025 §1202 rules ›
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Calculators›Individuals›Life-Event W-4 Helper
IND-04Inputs: Life eventsEstimate only

Life-event W-4 helper

A big life change usually means your paycheck withholding is wrong. Pick everything that changed this year and get a personalized checklist of exactly what to update on your Form W-4.

Select all that apply

Your W-4 action checklist

Want the exact dollar amount, not just the steps? Run the withholding checkup, then let's make sure your whole year is dialed in.
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General guidance, not tax advice, and not a substitute for the IRS Tax Withholding Estimator or a completed Form W-4. Your employer adjusts withholding based on the W-4 you submit; changes take effect on future paychecks only. The dependent amount shown reflects the 2026 child tax credit ($2,200 per qualifying child under 17) and $500 per other dependent, and phases out above $200,000 of income ($400,000 if married filing jointly). Confirm with a CPA before making changes, especially with multiple jobs, self-employment income, or a working spouse.

More for individuals

All 12
IND-01Withholding CheckupCompares federal withholding to the estimated tax on your return and suggests a Form W-4 change.Individuals IND-02California Take-Home PayGross pay to net pay after federal tax, FICA, California tax and SDI.Individuals IND-03Itemize vs. Standard DeductionCompares itemized deductions with the standard deduction and uses the larger.Individuals