Contact

If you have spotted a mistake, have a question about how a calculator works, or want to suggest a new tool, contact the site administrator by email. Please do not send sensitive medical, financial, identity or other confidential information.

Contact details

When you report an issue

It helps a lot if you include:

• The name of the calculator and a link to the page.
• The numbers you entered and the result you got.
• What you expected instead, and (if you can) the formula or source you are comparing it with.

With those details it is usually possible to check the formula, the rounding and the assumptions quickly.

Privacy and rights enquiries

You may also use this address to raise a privacy concern or report material that you believe infringes your intellectual-property rights. Include the relevant page URL and enough detail for the concern to be reviewed.

Suggestions

Ideas for new calculators or clearer explanations are useful too. If a result or explanation is confusing, describing what was unclear is often enough to improve it for everyone.