Terms of use
Use the calculators, quote the numbers, embed the widgets, call the API. All of it is free, including commercially, and none of it needs an account or a key. What follows is the short list of what that does and does not mean.
Terms last reviewed · How we check
What a number here is
Every figure is produced by a fixed evaluator from inputs you can see, using a formula printed on the same page, from a source that is named. No answer is generated by a language model. That is a strong claim about the arithmetic and a deliberately narrow one: it says the multiplication is right, not that the formula is the right one for your situation.
Three kinds of figure that are estimates
- Prices are ranges from published surveys with a stated year. They move with your region and the month, and they are not a quote.
- Anything describing a body — BMI, body fat, calorie needs, due dates — is a screening estimate from a published formula, not a diagnosis and not medical advice. The page names the body that published the formula so you can see which method produced the number.
- Anything describing money — a payment, a schedule, an affordability ratio — is arithmetic on the figures you entered, not advice about whether to borrow. Lenders apply their own rules on top.
Where a figure is an estimate the page says so beside the figure rather than in the small print, which is the only place a caveat does any good.
Using the numbers elsewhere
Quote them, print them, put them in a quote to a customer. Link back to the page the figure came from rather than to the homepage — that page carries the formula, the source and the date it was last checked, so your reader can check the figure instead of taking it from you.
The embeddable widgets carry a credit link inside them, and that link is the one condition on their use. The JSON endpoint and MCP tools have no key and no rate card; they are cached at the edge, so a busy page of yours is not a busy origin of ours. See the page for publishers.
No warranty, and what to do instead
The site is provided as it is, without warranty, and the arithmetic being right does not make it the right arithmetic for a decision that matters. For anything structural, medical or legally binding, the number here is a check on a professional’s figure, not a replacement for one.
A wrong number is a bug and the most useful thing you can report. Answering No to “Did this answer your question?” at the foot of a calculator records which page it came from.
Privacy · How we check · About