Contact
Report a problem, suggest a tool, or ask about anything on the site.
Get in touch
Email us at:
There is no contact form, because a form needs a server to receive it and this site does not run one — which is the same reason nothing you type into a tool is ever uploaded.
Reporting a wrong result
This is the most useful message you can send. To let us reproduce it, please include:
- Which tool, and a link to the page.
- The exact values you entered, including the units and any options you selected.
- The result you got, and the result you expected.
- Where your expected figure comes from, if there is a source.
Every calculation on the site is covered by tests, so a genuine error usually means a case nobody thought to test — which is exactly what we want to hear about.
Suggesting a tool
Suggestions are welcome, particularly with a sentence about what you were trying to do. Knowing the actual task makes the difference between a tool that helps and one that technically works.
What we cannot help with
- Financial, medical, tax or legal advice. The tools produce estimates; a qualified professional produces advice.
- Recovering data you entered into a tool. It never left your browser, so we do not have it.
- Questions about a specific advertisement. We do not control which ads are shown.