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Contact

Corrections, questions and bug reports

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Email

The fastest way to reach us is by email. There is no contact form on this site, and no phone line.

This is a one-person project, so replies usually take a few business days. Thanks for your patience.

If you are reporting a wrong number

Those reports are the most useful thing you can send, and they get fixed first. To help us reproduce it, please include:

A screenshot is welcome, but the typed-out inputs are what let us actually reproduce the issue.

What we cannot help with

This site is an estimating tool, not an engineering service. We cannot design your slab, check your structure, size your bars, or interpret your local building code. Those questions need a licensed engineer or your project's designer — please do not rely on an email reply from this site for anything structural.

If you bought through a link on this site

Any purchase is a contract between you and the retailer, not with us. For anything to do with an order — status, shipping, faults, returns — go straight to the retailer's own customer service; they are the only party who can act on it. If you think a link on this site is broken or pointing somewhere it should not, do tell us and we will fix it.

Privacy

Emails you send us are used only to answer your enquiry. See the privacy policy for how this site handles data, and the about page for how the calculator works.