Contact
Report a problem, suggest a tool, or ask a question.
Write to [email protected]. There is no contact form and no chat widget — an email reaches the person who maintains the site directly.
Reporting an incorrect result
This is the most useful message you can send. Include the tool, the values you entered and the result you expected. Calculation bugs are treated as the highest priority, because a calculator that is quietly wrong is worse than one that is missing.
Suggesting a tool
Tell us what you are trying to do rather than only naming the tool. Knowing the actual task usually leads to something more useful than the feature originally requested.
Privacy requests
For access to or deletion of data, or any question about how the site handles information, use the same address and mention privacy in the subject line.
Last updated: 15 August 2026