Contact
One person reads this inbox, so please be specific and you will get a useful answer.
Last updated: 8 October 2026
There is no contact form here on purpose — a form would need a server, and the whole point of this site is that it does not have one handling your data.
Reporting a wrong result
This is the most useful email you can send, and it gets priority. To let us reproduce it, please include:
- Which tool, and a link to it.
- The exact values you entered, including the unit system.
- The result you got, and the result you expected.
- Where your expected figure came from, if it was another calculator or a formula.
Every tool is covered by automated tests, so a confirmed error becomes a new test case before it is fixed — which means it cannot silently come back.
Requesting a tool
Tell us what you are trying to work out and what you currently use instead. Knowing the real task is far more useful than a tool name, because it often turns out an existing tool just needs one more input.
Privacy and data requests
Use the same address. Note that we hold no accounts and never receive what you type into a tool. If you have emailed us, your message and email address may be held so we can respond. See the privacy policy.