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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 ›
When a tool isn’t enoughEvery calculator links to the service or model that covers the rest of the question.Send an inquiry

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 ›
Rather have me run it?I can build the reporting package or run the analysis as an engagement.Send an inquiry
Services›Tax

Tax preparation and planning

I prepare federal and California returns for individuals and S-corporations, and I plan the year ahead so tax is part of the decision, not an afterthought.

Send an inquiry Try the Withholding Checkup calculator
Federal1040 · 1120-S
California540 · 100S
Starts withAn engagement letter

Who this is for

W-2 employees with investments, equity compensation or rental property

Sole proprietors and single-member LLCs filing Schedule C

S-corporation owners who want the 1120-S, the K-1 and their personal return prepared together

Real estate investors with rental activity, depreciation and passive-loss questions

What I prepare

Form 1040 and California Form 540
Wages, investments, self-employment income (Schedule C and SE), and rental activity (Schedule E).
Form 1040 / 540
Form 1120-S and California Form 100S
S-corporation returns, shareholder K-1s, and the basis and distribution records that support them.
Form 1120-S / 100S
Estimated payments
Quarterly federal and California estimates, set using the prior-year safe harbor or current-year projections.
IRC §6654
Extensions
Form 4868 and Form 7004 when a complete return isn't ready by the deadline, with the payment estimate that goes with it.
Form 4868 / 7004

What I look at before filing

Owner compensation
For S-corporations, whether shareholder wages are reasonable for the work performed (Rev. Rul. 74-44).
Rev. Rul. 74-44
The §199A deduction
Qualified business income, the wage and property limits, and whether the business is a specified service trade or business.
IRC §199A
Shareholder basis
Stock and debt basis under IRC §1366 and §1367, which limits the losses you can deduct and decides whether distributions are taxable.
IRC §§1366–1367
Depreciation choices
Bonus depreciation, §179 and cost segregation, and where California doesn't follow the federal rules.
IRC §§168, 179

I don't prepare C-corporation (Form 1120) or partnership (Form 1065) returns. If you aren't sure how your business is taxed, say so in your inquiry and I'll confirm whether it's a fit. Returns for other states are reviewed for scope before I accept an engagement.

Questions

What does it cost?

The fee depends on the return, the condition of the records and what's involved. I set the scope and fee in the engagement letter before any work begins.

What happens after I send an inquiry?

I reply by email to learn what you need. If it's a fit, you get an engagement letter and the IRC §7216 consent forms to sign, then a secure portal invitation for your documents.

Can I email my documents?

No. Tax documents go through the secure client portal only.

Calculator · IND-01

Withholding Checkup

Compares federal withholding to the estimated tax on your return and suggests a Form W-4 change.Calculator · BUS-02

1099 Estimated Tax Planner

Quarterly federal and California estimates using the 90%, 100% or 110% safe harbor, with an option for uneven income.Calculator · IND-03

Itemize vs. Standard Deduction

Compares itemized deductions with the standard deduction and uses the larger.

A question about your return? Ask me.

Send a few sentences. If it fits, you get an engagement letter with the scope and fee, and the IRC §7216 consent forms. Documents go through the secure portal.

Send an inquiry