Privacy Policy

TableSigma (“we”, “us”) provides free interactive statistics reference tables and calculators at tablesigma.com. This page explains what information the site collects and how it is used.

Values you type into a table or calculator

TableSigma does not require an account. Every z, t or chi-square value, degrees-of-freedom number, or contingency-table entry you type into a table or calculator is processed entirely inside your own browser using JavaScript — it is never sent to, or stored on, our server. Closing the tab clears it. This is true for every lookup tool on the site, including the z table, the t-test calculator, and the chi-square tools.

What we do collect

We do collect information in these specific cases:

• Contact form: if you send us a message, we store the name, email address, topic and message you submit, so we can read and reply to it.
• “Report an error” form: if you flag a possible mistake in a table, we store the table page, the value you mention, and your message, so we can review and fix it.
• “Worked examples” submissions: if you submit a worked example to share on a table page, we store the text and the name you provide (or “A reader” if left blank). Submissions are reviewed before they are shown publicly.
• Standard server logs: like most websites, our hosting and security infrastructure automatically logs basic request information (such as IP address and browser user-agent) for security and troubleshooting. These logs are not linked to form submissions.

Cookies

TableSigma does not currently run advertising cookies or third-party analytics cookies. If that changes — for example, if display advertising is added later — this page will be updated first, and the type of cookie, its purpose and an opt-out method will be listed here. WordPress may set a short-lived technical cookie if you interact with certain site features (such as the comment-preview system); these are functional only and do not build an advertising profile. Because TableSigma does not use tracking cookies today, there is nothing to opt out of; most browsers also let you block cookies globally in their privacy settings.

Who sees this data

Form submissions are stored on our own server and reviewed by the team that maintains TableSigma. Traffic to the site passes through Cloudflare, a content delivery and security network, which helps route requests to our server and protect the site from abuse. We do not sell or share your information with advertisers.

How long we keep it

Contact messages and error reports are kept as long as needed to review and act on them, and are deleted periodically afterward. Published worked examples remain visible until removed at the submitter’s request or by moderation.

Children’s privacy

TableSigma is a general-audience reference tool and does not knowingly collect personal information from children.

Your rights (GDPR / CCPA)

If you are in the EU/UK (GDPR) or California (CCPA), you have the right to ask us to access, correct or delete personal information you submitted through our forms, and to know what categories of data we hold about you. Since TableSigma does not sell personal data and does not use tracking cookies, most CCPA “do not sell” requests do not apply — there is nothing being sold. To exercise any of these rights, use the Contact page.

Changes to this policy

If this policy changes, the updated date below will be revised.