Free tools
Run the numbers before you decide
Preparer-grade calculators for the questions that actually cost money — what to pay in estimates, what an S corp salary should be, how much can go into a retirement plan. Built for the 2026 tax year.
Why these exist
Most tax calculators online answer a simpler question than the one you have. They apply one bracket table and stop, which is fine until the answer depends on the qualified business income deduction phasing out, or on capital gains stacking on top of ordinary income, or on which of the two safe harbour tests you actually meet.
These do the full computation, the way it would be done on a return. Every one of them runs entirely in your browser: nothing you enter is transmitted anywhere, stored, or seen by me.
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The calculators
All free, all current for the 2026 tax year. Each one prints to a clean worksheet you can keep with your records or hand to your preparer.
Estimated Tax Calculator
Whether you owe quarterly estimates, how much, and by when — with the penalty safe harbour worked out rather than guessed.
- Both safe harbour tests, including the higher percentage that applies above the prior-year income threshold
- A four-quarter payment schedule with the due dates
- Tells you which test is cheaper for your situation
Income & Tax Projection
A full 1040 projection for the year — what you will actually owe, not what a bracket table suggests.
- Self-employment tax, the SALT cap phase-down and additional Medicare tax
- Qualified business income with the wage limit and the specified-service phase-in
- Qualified dividends and long-term gains layered on top of ordinary income, plus net investment income tax
S Corp Owner Compensation Optimizer
Once the election is made: what salary to take, compared on net cash after all taxes rather than on tax saved.
- A sole proprietorship baseline against five salary levels, side by side
- A reasonable-compensation build-up you can put in the file if the number is ever questioned
- Flags any salary that falls below what the build-up supports
S Corp vs LLC
Before the election: whether to make it at all, on your numbers, after the payroll you would have to run and the cost of the 1120-S.
- Compares cash left in your pocket, not tax saved — the two answers differ once the payroll service and the extra return are counted
- Shows the profit at which the election starts paying for itself, so a business too small for it is told so
- Accounts for what paying yourself a salary does to your qualified business income deduction, which is where most comparisons quietly go wrong
Five-Year Tax Bracket Calculator
Where your income actually falls — how much of it is taxed at each rate, for any year from 2022 to 2026.
- Shows the income sitting in every band, including the ones you are nowhere near
- Separates your marginal rate from your effective rate, which are different numbers and only one of them is what you pay
- Runs the same income through all five years, so you can see what indexing and the 2025 rule changes were worth
Self-Employed 401(k) Maximizer
How much you can actually put away this year through a solo 401(k), employee and employer sides both.
- Handles the circular calculation between the deduction and the contribution
- Separates the elective deferral from the employer contribution
- Prints a worksheet showing how the figure was reached
Before we start work
Engagement letter
Not a calculator — the document that sets out what I will do, what I need from you, and what it costs. Build yours, read it, print it.
Engagement Letter Builder
Tick the returns, schedules and states that apply to you, choose the fee arrangement, and the full letter assembles itself — ready to read, print and sign.
- Individual (Form 1040) and business entity returns, with the scope page built from what you tick rather than written in narrative
- All eight sections: scope, your responsibilities, professional standards and tax positions, fees, audits and third-party requests, limitation of liability, dispute resolution, acceptance
- Prints the whole letter, or just the scope page as an attachment to one you already have
- Runs entirely in your browser, like everything else here — nothing is submitted and no account is created
Nothing is collected
These run in your browser
No account, no email, no download. Every calculation happens on your own device, and nothing you enter is sent anywhere — which is why there is no “email me my results” button. Print the worksheet if you want a copy.
Also on the site
The explainers behind the maths
Every calculator has an article and a short video covering the rule it applies — worth ten minutes before you act on a number.
A number is not a decision
Want someone to check it?
A calculator tells you what the rule produces for the figures you typed. Whether those are the right figures, and whether there is a better position available, is a conversation — and the first one is free.
These calculators are general tax education and do not constitute individualized tax, legal or financial advice. Figures are stated for the tax year shown and are subject to IRS adjustment — verify against current guidance before acting.