This is not tax advice

This is an estimate, not tax advice

Everything on this site is a calculation offered for planning. It is not tax advice, it does not create a professional relationship, and nobody here is acting as your adviser, accountant or attorney.

The difference is not a formality. Advice takes account of your particular circumstances and carries responsibility for the outcome. A calculator applies published rates to the figures you typed and carries neither — it cannot know whether a child meets a residency test, whether an expense was ordinary and necessary, or whether a salary is reasonable for the work performed.

Use these figures to orient yourself: to compare two offers, to see whether April is likely to bring a refund or a bill, to understand what a state or a county costs. Do not use them to file, to sign anything, or to settle a question that turns on your specific facts.

Where a decision has real money or real consequences attached, a licensed professional is worth what they charge — and several of the pages here say so at the point where the calculator stops being the right tool.

What the calculators do not model

The general income tax calculator assumes a salaried worker taking the standard deduction, which describes roughly nine in ten filers and describes the rest badly. It does not model itemised deductions, capital gains, or most credits.

Each specialist calculator states its own boundaries under the result: the rental one does not model cost segregation, 1031 exchanges or depreciation recapture on sale; the small business one does not model state entity taxes; the retirement one does not model required minimum distributions or the Medicare income-related surcharge; the capital gains one does not model collectibles, qualified small business stock or wash sales.

None of them models the alternative minimum tax, equity compensation, foreign income, trusts, or estates. None handles a partial-year residency split between states.

Local income tax is covered for 3,672 jurisdictions across 7 states, which is more than almost anything else models and is still not every jurisdiction that levies one.

Where a figure has not been verified against a primary source, the page says so. That is a statement about our data and not about the law: it means we have not checked, not that nothing exists.

Accuracy, and what happens when we get it wrong

We check every figure against the authority that publishes it and record the date. We also make mistakes — several are documented publicly on the corrections page, including publishing one county's property rate on another county's page and nearly publishing withholding rates as if they were statutory rates.

The figures are provided without warranty. Tax law changes, sometimes mid-year and sometimes with retroactive effect, and a figure that was correct when verified can be superseded before you read it. The verification date on each page is what tells you how much confidence that particular number has earned.

We are not liable for decisions made on the basis of these estimates. That is the ordinary position for a free planning tool, and it is the reason the previous section exists: knowing what is not modelled is what makes an estimate usable.

If you find something wrong, the corrections page is the fastest route and we would rather be told than be right. Corrections are published with the date and what was affected, not applied quietly.

When you need a professional rather than a calculator

A business with expenses to characterise, or any question about whether an entity election is worth it. A rental, particularly at purchase or sale. Equity compensation of any size — restricted stock, options, or anything with an alternative minimum tax dimension.

A move between states part-way through a year, or work performed across a state line. An inheritance, a trust, or income from outside the United States. A year with a notice from a tax authority in it.

Anything where the answer depends on a judgement about your facts rather than on arithmetic over your figures. That is the dividing line, and a calculator is on the wrong side of it by construction.

For setting a W-4 specifically, the IRS Tax Withholding Estimator is the authoritative free tool and is better than this one for that job — we say so on its own page too.

Questions

Is this tax advice?

No. It is a calculation offered for planning. It does not take account of your particular circumstances, does not create a professional relationship, and carries no responsibility for the outcome. Advice does all three, which is what you are paying for when you buy it.

Can I file my return from these numbers?

No. This is not a filing tool and does not produce a return. Use filing software, IRS Free File, or a preparer. The estimate is useful for knowing roughly what to expect before you get there.

Are the figures guaranteed to be correct?

No. They are verified against the authority that publishes them, with the date recorded on each page, and they are provided without warranty. Tax law changes mid-year and sometimes retroactively, so a figure correct when verified can be superseded before you read it.

What if I find a mistake?

Report it on the corrections page. We publish every correction with the date and what it affected rather than fixing things quietly, and we would rather be told than be right.

When should I see a professional instead?

When the answer depends on judgement about your facts rather than arithmetic over your figures: a business, a rental, equity compensation, a mid-year move between states, an inheritance, foreign income, or a notice from a tax authority.