This page explains what happens to the numbers you type into a calculator on this site, plus the ordinary web traffic that comes with visiting any page here.
Every tool on StatsCalc, sample size, standard deviation, p-value, confidence interval, z-score, probability and the rest, runs on JavaScript that executes entirely on your own device. When you paste a list of numbers into the standard deviation calculator or type a sample mean into the confidence interval tool, that value is read once, computed against locally, and displayed back to you. There is no submit button that sends it anywhere, no server-side calculation step, and no database row created for it. Closing the tab or reloading the page erases whatever you entered.
Standard web and analytics logs record which pages were requested, an approximate location derived from IP address, browser and device type, and the referring site. This is ordinary traffic data, not the contents of any calculator field, and we use it only to see which tools get used and to spot pages that are slow or broken.
Google Analytics and Google AdSense both set cookies on this site. Analytics cookies show us aggregate usage patterns and do not identify you by name. AdSense cookies may be used by Google to serve ads based on your browsing history across other sites; you can turn ad personalization off in your Google account, or reject cookies through the banner shown on first visit. Every calculator on this site works the same whether you accept or reject cookies, since none of them depend on a cookie to produce a result.
Messages sent through the contact form are handled by a third-party processor, Web3Forms. Your name, email address, and message text are used only to reply to you; we do not add senders to a mailing list or share that information with anyone else.
A small number of outbound links on this site are affiliate links. If you click one and buy something, we may earn a commission at no extra cost to you. That has no bearing on how a calculator computes your result.
This site is built for students, researchers, and anyone else doing statistics work, not specifically for children, and we do not knowingly collect information from anyone under 13.
If how this site handles data changes, a new analytics tool or a new ad network, we update this page and the date at the top. We do not send an email notice, since we do not collect email addresses outside the contact form.