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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.

All models

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›Withholding Checkup
IND-01Inputs: Pay, withholding, filing statusEstimate only

2026 federal withholding checkup

Estimate your 2026 federal income tax, compare it to what's being withheld from your pay, and see how to adjust your W-4 to land where you want at filing time.

How your income fills the 2026 brackets

Withholding vs. projected tax

Want a real W-4 and estimated-tax plan for your situation? This is a federal estimate — let's get the whole picture right.
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Estimate only, for planning — not tax advice or a substitute for IRS Form W-4 or the IRS Tax Withholding Estimator. Covers federal income tax withholding using 2026 brackets and the standard deduction (Rev. Proc. 2025-32). It excludes Social Security and Medicare (FICA), California and other state withholding, itemized deductions, multiple-job effects, the QBI deduction, other credits and income, and AMT. California withholding is calculated separately. Confirm your situation with a CPA before changing your withholding.

More for individuals

All 12
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 IND-04Life-Event W-4 HelperA checklist of Form W-4 changes after a marriage, a new child, a home purchase or a side job.Individuals