Privacy Policy
Last updated October 27, 2026.
What we collect
The calculators run entirely in your browser. The numbers you type are not sent to us or to anyone else. There are no accounts, and the site does not set cookies or use analytics or advertising at this time.
Information saved on your device
To make the site more useful, it saves a few things in your browser's local storage on your own device: the values you enter in calculators and tools, the ticks and notes on checklists, and a copy of the site's pages so it can work offline. This information stays on your device. We cannot see it, and it is not sent anywhere. You can clear it at any time through your browser's settings (clear site data), or with the "Reset to defaults" and "Clear all ticks" buttons. If you use a shared computer, clear it when you finish.
Links you copy with "Copy link to these values" contain the values you entered. Be careful about sharing a link if the values are confidential.
Server logs
The site is delivered through Cloudflare. Like most web hosts, Cloudflare processes technical information such as IP addresses and requested pages in order to serve the site and protect it from abuse. See Cloudflare's privacy policy for details.
If you email us, we receive your email address and message and use them only to reply.
Changes
If we add advertising, analytics, cookies or user accounts, this policy will be updated first, and where the law requires it we will ask for your consent before any non-essential cookies are used.
Contact
Questions about this policy: see the contact page, or email hello@controlstoolbox.com.