Contact

There is no contact form here, because a contact form would mean collecting and storing what you type — and the whole point of this site is that it does not do that. Email works perfectly well.

What to write about

• Report a wrong answer. Tell us the calculator, the numbers you entered and the figure you expected. Anything that produces a wrong result gets fixed first.
• Suggest a calculator. If you keep opening a spreadsheet for the same sum, we would like to hear about it. Requests genuinely shape what gets built next.
• Ask about privacy. Questions about what the site stores, or requests relating to data protection, are answered by the same address.

Before you write about a result

Every calculator page documents the exact formula it uses, along with worked examples. Differences usually come down to convention rather than arithmetic — for example whether an A+ is worth 4.0 or 4.3, or whether a tip is taken before or after sales tax.

If the formula on the page is not the one your school, employer or tax authority uses, say so in your message and tell us which convention you need. That is useful information even when nothing is broken.

Response times

Advanced Calculator is a small project rather than a company, so replies are usually within a few days. Reports of incorrect results are prioritised over everything else.

Business and advertising

Advertising, partnership and licensing enquiries go to the same address. Please put the topic in the subject line so it does not get lost among the bug reports.