About SmallBizCalci

What this tool does

You enter what a job or a product actually costs you — materials, your own hours at your own rate, job extras, and a share of your monthly overhead — along with the profit margin you want and the percentage a payment processor takes. It returns the price you would have to charge to end up with that margin, and shows every step of the arithmetic so you can check it.

That is the whole product. There is no account, no trial, no upsell, and no feature that unlocks later.

Why it exists

Most pricing goes wrong in the same two places.

The first is markup being mistaken for margin. Multiply your cost by 1.30 and you have added a 30% markup, which leaves you a 23% margin — and once a card processor takes its cut, less than that. Wanting a 30% margin means dividing by 0.70, not multiplying by 1.30. The gap looks small on one invoice and is the difference between a business that works and one that does not across a year.

The second is unpaid time. Owners routinely leave their own labour out of the cost, or count only the hours that felt like work, and then wonder why a busy month produced no money. This calculator makes labour a cost line you cannot skip past.

Who it is for

Freelancers, contractors, cleaners, landscapers, photographers, designers, handymen, online sellers and small retailers — anyone quoting a job or pricing a product without a finance department behind them. The presets cover common trades as starting points; every field stays editable, because nobody else's numbers are yours.

How the numbers are worked out

Every formula the tool uses is written out in full on the How we calculate section, including how rounding is handled and how sales tax is kept separate from your revenue. Nothing is estimated behind the scenes.

The arithmetic runs in fixed-point decimal rather than ordinary floating-point numbers, so the same inputs always produce exactly the same price and the breakdown always reconciles to the penny. The calculation code is covered by an automated test suite that checks it against hand-worked examples, an independent implementation of the published formula, and several hundred randomised scenarios.

What it deliberately is not

• It is not tax, accounting, legal or financial advice. It is arithmetic on the numbers you type in. Decisions about your business are yours, and a qualified professional is worth their fee.
• It does not know your market. The result is the price that hits your target, not proof that a customer will pay it. If the number comes out far above local rates, that is information about your costs or your hours, not a verdict.
• It does not model everything. Income tax, payroll taxes, self-employment tax, import duties, discounts, refunds and shipping surcharges are outside its scope.

Privacy, briefly

The calculator runs entirely in your browser. The figures you type are never sent to a server, there are no analytics, no advertising, no cookies and no third-party scripts of any kind. Your inputs are kept only for the current browser tab so the page can remember them while you work, and they are gone when you close it. The privacy policy sets this out in full.

Corrections

If a result looks wrong, that is worth knowing about — accuracy is the only thing this tool has to offer. Send the numbers you entered and the figure you expected via the contact page.