Contact
Have a question about a calculation or found an error in a guide?
Write to [email protected]. Please include the page URL, the measurements you entered and what you expected to see. Do not send payment information or sensitive personal details.
What we can help with
- Reporting a broken calculator or incorrect example.
- Suggesting a project calculation that would be useful to makers.
- Asking about site content or privacy.
Calculator estimates are general planning aids. We cannot inspect your materials or guarantee the outcome of an individual project by email.