Privacy policy

Effective October 25, 2026.

Calculator and practice data

Calculations and practice checks run locally in your browser. The site does not send your numerical entries or practice scores to a calculation service. It does not require an account and does not store these entries in cookies or local storage.

Server access logs

Like other websites, our hosting server receives technical information when you request a page, including an IP address, requested URL, time, browser user-agent and possibly a referring page. Logs support security and service diagnosis. This version does not include third-party analytics or advertising scripts.

Contact email

If you email us, your email provider and ours process the message, and we receive the address and information you choose to send. Please send only the information needed to explain the issue.

Students and children

We do not ask for student identities, school details or dates of birth. A child should ask a parent or guardian before sending a contact email. Do not include personal information in calculator fields.

External links and changes

Reference links lead to other websites with their own policies. If analytics, advertising or other data processing is added, this policy will be updated before those features are activated. For privacy questions, use the contact page.