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Calculators

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

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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›Business owners›QBI Deduction Estimator (§199A)
BUS-04Inputs: QBI, taxable income, W-2 wages, SSTBEstimate only

QBI deduction estimator (§199A)

Pass-through owners can deduct up to 20% of qualified business income — now permanent under the 2026 rules. This estimates yours, including the income thresholds and the rules for service businesses.

Net pass-through profit (Schedule C, K-1, rental).
Roughly your taxable income before this deduction.
Optional — these reduce the income cap.
Only matters above the income threshold.
Optional — unadjusted basis of business property.
QBI planning is where real money is made or lost. Salary, wages, and entity choice all move this number — let's optimize it.
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Estimate only, for planning — not tax advice. Uses 2026 §199A thresholds (Rev. Proc. 2025-32): $201,775 (single/HOH/MFS) and $403,500 (MFJ), with the limits fully phasing in $75,000 / $150,000 above. Below the threshold the deduction is 20% of QBI, capped at 20% of taxable income less net capital gains. Above it, non-service businesses are limited to the greater of 50% of W-2 wages or 25% of wages plus 2.5% of qualified property (UBIA), and service businesses (SSTBs) lose the deduction entirely; within the range, both phase in. A $400 minimum applies to active owners with at least $1,000 of QBI. The deduction does not reduce self-employment tax, and California does not allow it. Confirm with a CPA.

More for business owners

All 12
BUS-01S-Corp vs. Sole ProprietorEstimates self-employment tax savings from an S election, after a reasonable salary and the cost of running payroll.Business owners BUS-021099 Estimated Tax PlannerQuarterly federal and California estimates using the 90%, 100% or 110% safe harbor, with an option for uneven income.Business owners BUS-03Solo 401(k) and SEP-IRAMaximum contribution under each plan by entity type and age, and which plan allows more.Business owners BUS-05Entity ComparisonSole proprietorship, S-corporation and C-corporation compared on the same profit, with optional California entity taxes.Business owners