We read every message. Use the address below for questions, corrections, partnership enquiries and calculator requests.
Requesting a calculator
If there is a calculation you need that is not on the site yet, email us and include:
- What you want to work out, in plain words.
- The values you would enter and the result you expect.
- A formula or source, if you have one.
Reporting an error
If a result looks wrong, tell us which calculator it was, the values you entered and the answer you expected. That lets us reproduce and fix the problem quickly.
We aim to reply within a few working days.